Android Phase D: Project foundation, Room DB, Retrofit API, Hilt

- Android CLI Setup: initialized empty-activity app (AGP 9.0, Kotlin 2.3.20) - Version catalog: Compose BOM 2026.03.01, Material 3, Hilt 2.60.1, Room 2.7.2, Retrofit 2.11.0, OkHttp 4.12.0, WorkManager 2.10.2, Kotlinx Serialization - Room Database (v1): ListEntity, ItemEntity, OpLogEntity - Room DAOs: ListDao, ItemDao, OpLogDao with LWW upsert queries - Network layer: MitbringslApi Retrofit interface + DTOs + AuthInterceptor - Dependency Injection: DatabaseModule, NetworkModule, RepositoryModule, HiltAndroidApp - Build verification: assembleDebug & test green ✅
2026-08-05 20:09:34 +02:00 · 2026-08-05 20:09:34 +02:00 · e44d645112
commit e44d645112
parent 895725b5e5
57 changed files with 2090 additions and 26 deletions
--- a/AGENTS.md
+++ b/AGENTS.md
@ -164,9 +164,9 @@ Legende: ✅ erledigt · 🚧 in Arbeit · ⬜ offen
      `upsertItemName` in Projektion (innerhalb Push-Transaktion).
 - ✅ **Phase C – Caddy:** `Caddyfile.behind-proxy` (auto_https off, trusted_proxies),
      `CADDY_HTTP_PORT`/`CADDY_HTTPS_PORT` in docker-compose.
- ⬜ **Phase D – Android-Fundament:** Gradle (Kotlin DSL, Version Catalog, Hilt/KSP, Compose BOM),
-      Theme, Nav, Room.
- ⬜ **Phase D – Repository + Retrofit-API + DTOs.**
+- ✅ **Phase D – Android-Fundament:** Gradle (Kotlin DSL, Version Catalog, Hilt/KSP, Compose BOM, Room, Retrofit, WorkManager), Theme, Nav.
+      **Verifiziert:** `./gradlew assembleDebug` und `./gradlew test` erfolgreich.
+- ✅ **Phase D – Repository + Retrofit-API + DTOs:** Room DB (`lists`, `items`, `op_log`), DAOs (LWW upsert), `MitbringslApi`, AuthInterceptor, Hilt Modules (`DatabaseModule`, `NetworkModule`, `RepositoryModule`).
 - ⬜ **Phase D – Login-Screen** (eigene User + Google Credential Manager + Generic OIDC PKCE).
 - ⬜ **Phase E – SyncEngine** (OutboxDrain + CursorPull via WorkManager), HLC client-side.
 - ⬜ **Phase E – Listen-Übersicht + Detail + AddItemBar (Autocomplete) + Settings.**
@ -174,27 +174,16 @@ Legende: ✅ erledigt · 🚧 in Arbeit · ⬜ offen
 - ⬜ **Phase F – README + docs** (ARCHITECTURE/SYNC/API).

 ### Wo genau weitermachen?
-**Phase C ist komplett ✅. Nächster Schritt = Phase D (Android-Fundament).**
+**Phase D (Fundament + Repositories) ist komplett ✅. Nächster Schritt = Phase D Login-Screen / Phase E SyncEngine.**

-Phase C erledigt:
- ✅ `internal/sync/hlc.go` – HLC (wall_ms<<16|counter, Tick/Now/After, global mutex).
- ✅ `internal/store/opstore.go` – AppendOps idempotent (ON CONFLICT DO NOTHING), LWW-Projektion
-  (list_create/rename/delete, item_add/update/remove), PullOps (cursor, 500er Pages).
- ✅ `internal/store/liststore.go` – CreateList / GetLists / GetList (owner-check MVP).
- ✅ `internal/store/itemstore.go` – GetItems (nicht-gelöschte Items einer Liste).
- ✅ `internal/store/suggeststore.go` – Search (pg_trgm fuzzy, LIKE-fallback, 10 Ergebnisse).
- ✅ `internal/httpapi/lists.go` – GET/POST /api/lists, GET /api/lists/{id} + Items.
- ✅ `internal/httpapi/ops.go` – POST /api/lists/{id}/ops (Push), GET /api/lists/{id}/ops (Pull).
- ✅ `internal/httpapi/suggest.go` – GET /api/suggestions?q=.
- ✅ `internal/httpapi/api.go` – alle Routen verdrahtet.
- ✅ `deploy/Caddyfile.behind-proxy` – auto_https off + trusted_proxies.
- ✅ `deploy/docker-compose.yml` – CADDY_HTTP_PORT / CADDY_HTTPS_PORT.
-
-Phase D – Android-Fundament (offen):
-1. Gradle-Setup: Kotlin DSL + `libs.versions.toml`, Hilt/KSP, Compose BOM, Room, Retrofit.
-2. Theme (Material 3) + Navigation (Compose Nav).
-3. Room-Datenbankschema (Listen/Items/OpLog/Outbox).
-4. Retrofit-API + DTOs passend zu den Backend-Endpoints.
+Phase D erledigt:
+- ✅ Android CLI Setup (`android create empty-activity`).
+- ✅ Version Catalog (`libs.versions.toml`) mit Compose BOM, Hilt, Room, Retrofit, OkHttp, WorkManager, Kotlinx Serialization.
+- ✅ AGP 9.0 Compatibility (Kotlin Plugin built-in).
+- ✅ Room DB (`AppDatabase`), Entities (`ListEntity`, `ItemEntity`, `OpLogEntity`), DAOs mit LWW Upsert (`ListDao`, `ItemDao`, `OpLogDao`).
+- ✅ Retrofit API Interface (`MitbringslApi`), DTOs (`Dtos.kt`), AuthInterceptor (Bearer Token Injection).
+- ✅ Hilt Dependency Injection (`DatabaseModule`, `NetworkModule`, `RepositoryModule`, `@HiltAndroidApp MitbringslApp`).
+- ✅ Gradle build & unit tests verifiziert (`assembleDebug` & `test` grün).

 ---

@ -238,6 +227,6 @@ docker run --rm --network <net> \

 ## Git-Status
 - Repo initialisiert, Branch `main`. Remote ist konfiguriert (`origin`).
- Phase A + Phase B (vollständig) committed und gepusht.
- Phase C (Sync-Kern + Caddy behind-proxy) committed und gepusht. **Phase C vollständig ✅.**
- Nächster Schritt: **Phase D – Android-Fundament** (siehe Roadmap oben).
+- Phase A + Phase B + Phase C committed und gepusht.
+- Phase D (Android-Fundament, Room DB, Retrofit API, Hilt Setup) committed und gepusht. **Phase D Fundament vollständig ✅.**
+- Nächster Schritt: **Login-Screen / Phase E SyncEngine** (siehe Roadmap oben).
--- a/android/.gitignore
+++ b/android/.gitignore
@ -0,0 +1,17 @@
+*.iml
+.gradle
+/local.properties
+/.idea/caches
+/.idea/libraries
+/.idea/modules.xml
+/.idea/workspace.xml
+/.idea/navEditor.xml
+/.idea/assetWizardSettings.xml
+.DS_Store
+/build
+/captures
+.externalNativeBuild
+.cxx
+local.properties
+*.jks
+*.keystore
--- a/android/app/.gitignore
+++ b/android/app/.gitignore
@ -0,0 +1 @@
+/build
--- a/android/app/build.gradle.kts
+++ b/android/app/build.gradle.kts
@ -0,0 +1,125 @@
+plugins {
+  alias(libs.plugins.android.application)
+  alias(libs.plugins.compose.compiler)
+  alias(libs.plugins.hilt)
+  alias(libs.plugins.kotlin.serialization)
+  alias(libs.plugins.ksp)
+  alias(libs.plugins.room)
+}
+
+android {
+  namespace = "com.example.mitbringsl"
+  compileSdk = 36
+
+  defaultConfig {
+    applicationId = "com.example.mitbringsl"
+    minSdk = 26
+    targetSdk = 36
+    versionCode = 1
+    versionName = "1.0"
+
+    testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
+
+    // Backend base URL – override in release build or via local.properties
+    buildConfigField("String", "BASE_URL", "\"http://10.0.2.2:8080/\"")
+  }
+
+  buildTypes {
+    release {
+      isMinifyEnabled = true
+      proguardFiles(getDefaultProguardFile("proguard-android-optimize.txt"), "proguard-rules.pro")
+      // Override BASE_URL for production
+      buildConfigField("String", "BASE_URL", "\"https://mitbringsl.example.com/\"")
+    }
+  }
+
+  compileOptions {
+    sourceCompatibility = JavaVersion.VERSION_17
+    targetCompatibility = JavaVersion.VERSION_17
+  }
+
+  buildFeatures {
+    compose = true
+    buildConfig = true   // needed for BASE_URL injection
+    aidl = false
+    shaders = false
+  }
+
+  packaging {
+    resources {
+      excludes += "/META-INF/{AL2.0,LGPL2.1}"
+    }
+  }
+}
+
+// Room schema export directory
+room {
+  schemaDirectory("$projectDir/schemas")
+}
+
+kotlin {
+  jvmToolchain(17)
+}
+
+dependencies {
+  val composeBom = platform(libs.androidx.compose.bom)
+  implementation(composeBom)
+  androidTestImplementation(composeBom)
+
+  // Core Android
+  implementation(libs.androidx.core.ktx)
+  implementation(libs.androidx.lifecycle.runtime.ktx)
+  implementation(libs.androidx.activity.compose)
+
+  // Lifecycle / ViewModel
+  implementation(libs.androidx.lifecycle.runtime.compose)
+  implementation(libs.androidx.lifecycle.viewmodel.compose)
+
+  // Compose UI + Material3
+  implementation(libs.androidx.compose.ui)
+  implementation(libs.androidx.compose.ui.tooling.preview)
+  implementation(libs.androidx.compose.material3)
+  debugImplementation(libs.androidx.compose.ui.tooling)
+
+  // Navigation 3
+  implementation(libs.androidx.navigation3.ui)
+  implementation(libs.androidx.navigation3.runtime)
+  implementation(libs.androidx.lifecycle.viewmodel.navigation3)
+
+  // Hilt (DI)
+  implementation(libs.hilt.android)
+  ksp(libs.hilt.android.compiler)
+  implementation(libs.hilt.navigation.compose)
+
+  // Room (local DB – source of truth)
+  implementation(libs.room.runtime)
+  implementation(libs.room.ktx)
+  ksp(libs.room.compiler)
+
+  // Retrofit + OkHttp (network)
+  implementation(libs.retrofit)
+  implementation(libs.retrofit.serialization)
+  implementation(libs.okhttp)
+  implementation(libs.okhttp.logging)
+
+  // Kotlinx Serialization (JSON)
+  implementation(libs.kotlinx.serialization.json)
+
+  // Coroutines
+  implementation(libs.kotlinx.coroutines.android)
+
+  // WorkManager (background sync)
+  implementation(libs.workmanager.ktx)
+  implementation(libs.hilt.work)
+  ksp(libs.hilt.work.compiler)
+
+  // Tests
+  testImplementation(libs.junit)
+  testImplementation(libs.kotlinx.coroutines.test)
+  androidTestImplementation(libs.androidx.test.core)
+  androidTestImplementation(libs.androidx.test.ext.junit)
+  androidTestImplementation(libs.androidx.test.runner)
+  androidTestImplementation(libs.androidx.test.espresso.core)
+  androidTestImplementation(libs.androidx.compose.ui.test.junit4)
+  debugImplementation(libs.androidx.compose.ui.test.manifest)
+}
--- a/android/app/schemas/com.example.mitbringsl.data.local.AppDatabase/1.json
+++ b/android/app/schemas/com.example.mitbringsl.data.local.AppDatabase/1.json
@ -0,0 +1,305 @@
+{
+  "formatVersion": 1,
+  "database": {
+    "version": 1,
+    "identityHash": "c5e70cf816f82a65da0a30d8315b70e8",
+    "entities": [
+      {
+        "tableName": "lists",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` TEXT NOT NULL, `name` TEXT NOT NULL, `ownerId` TEXT NOT NULL, `createdAt` INTEGER NOT NULL, `updatedAt` INTEGER NOT NULL, `deletedAt` INTEGER, `hlcTs` INTEGER NOT NULL, PRIMARY KEY(`id`))",
+        "fields": [
+          {
+            "fieldPath": "id",
+            "columnName": "id",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "name",
+            "columnName": "name",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "ownerId",
+            "columnName": "ownerId",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "createdAt",
+            "columnName": "createdAt",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "updatedAt",
+            "columnName": "updatedAt",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "deletedAt",
+            "columnName": "deletedAt",
+            "affinity": "INTEGER"
+          },
+          {
+            "fieldPath": "hlcTs",
+            "columnName": "hlcTs",
+            "affinity": "INTEGER",
+            "notNull": true
+          }
+        ],
+        "primaryKey": {
+          "autoGenerate": false,
+          "columnNames": [
+            "id"
+          ]
+        },
+        "indices": [
+          {
+            "name": "index_lists_ownerId",
+            "unique": false,
+            "columnNames": [
+              "ownerId"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_lists_ownerId` ON `${TABLE_NAME}` (`ownerId`)"
+          },
+          {
+            "name": "index_lists_deletedAt",
+            "unique": false,
+            "columnNames": [
+              "deletedAt"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_lists_deletedAt` ON `${TABLE_NAME}` (`deletedAt`)"
+          }
+        ]
+      },
+      {
+        "tableName": "items",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` TEXT NOT NULL, `listId` TEXT NOT NULL, `name` TEXT NOT NULL, `quantity` TEXT, `checked` INTEGER NOT NULL, `sortOrder` INTEGER, `createdAt` INTEGER NOT NULL, `updatedAt` INTEGER NOT NULL, `deletedAt` INTEGER, `hlcTs` INTEGER NOT NULL, `clientId` TEXT, `checkedAt` INTEGER, PRIMARY KEY(`id`), FOREIGN KEY(`listId`) REFERENCES `lists`(`id`) ON UPDATE NO ACTION ON DELETE CASCADE )",
+        "fields": [
+          {
+            "fieldPath": "id",
+            "columnName": "id",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "listId",
+            "columnName": "listId",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "name",
+            "columnName": "name",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "quantity",
+            "columnName": "quantity",
+            "affinity": "TEXT"
+          },
+          {
+            "fieldPath": "checked",
+            "columnName": "checked",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "sortOrder",
+            "columnName": "sortOrder",
+            "affinity": "INTEGER"
+          },
+          {
+            "fieldPath": "createdAt",
+            "columnName": "createdAt",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "updatedAt",
+            "columnName": "updatedAt",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "deletedAt",
+            "columnName": "deletedAt",
+            "affinity": "INTEGER"
+          },
+          {
+            "fieldPath": "hlcTs",
+            "columnName": "hlcTs",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "clientId",
+            "columnName": "clientId",
+            "affinity": "TEXT"
+          },
+          {
+            "fieldPath": "checkedAt",
+            "columnName": "checkedAt",
+            "affinity": "INTEGER"
+          }
+        ],
+        "primaryKey": {
+          "autoGenerate": false,
+          "columnNames": [
+            "id"
+          ]
+        },
+        "indices": [
+          {
+            "name": "index_items_listId",
+            "unique": false,
+            "columnNames": [
+              "listId"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_items_listId` ON `${TABLE_NAME}` (`listId`)"
+          },
+          {
+            "name": "index_items_deletedAt",
+            "unique": false,
+            "columnNames": [
+              "deletedAt"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_items_deletedAt` ON `${TABLE_NAME}` (`deletedAt`)"
+          }
+        ],
+        "foreignKeys": [
+          {
+            "table": "lists",
+            "onDelete": "CASCADE",
+            "onUpdate": "NO ACTION",
+            "columns": [
+              "listId"
+            ],
+            "referencedColumns": [
+              "id"
+            ]
+          }
+        ]
+      },
+      {
+        "tableName": "op_log",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`localId` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, `listId` TEXT NOT NULL, `clientId` TEXT NOT NULL, `clientSeq` INTEGER NOT NULL, `opType` TEXT NOT NULL, `targetId` TEXT NOT NULL, `payload` TEXT NOT NULL, `hlcTs` INTEGER NOT NULL, `createdAt` INTEGER NOT NULL, `serverSeq` INTEGER, `synced` INTEGER NOT NULL)",
+        "fields": [
+          {
+            "fieldPath": "localId",
+            "columnName": "localId",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "listId",
+            "columnName": "listId",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "clientId",
+            "columnName": "clientId",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "clientSeq",
+            "columnName": "clientSeq",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "opType",
+            "columnName": "opType",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "targetId",
+            "columnName": "targetId",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "payload",
+            "columnName": "payload",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "hlcTs",
+            "columnName": "hlcTs",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "createdAt",
+            "columnName": "createdAt",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "serverSeq",
+            "columnName": "serverSeq",
+            "affinity": "INTEGER"
+          },
+          {
+            "fieldPath": "synced",
+            "columnName": "synced",
+            "affinity": "INTEGER",
+            "notNull": true
+          }
+        ],
+        "primaryKey": {
+          "autoGenerate": true,
+          "columnNames": [
+            "localId"
+          ]
+        },
+        "indices": [
+          {
+            "name": "index_op_log_listId",
+            "unique": false,
+            "columnNames": [
+              "listId"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_op_log_listId` ON `${TABLE_NAME}` (`listId`)"
+          },
+          {
+            "name": "index_op_log_clientId_clientSeq",
+            "unique": true,
+            "columnNames": [
+              "clientId",
+              "clientSeq"
+            ],
+            "orders": [],
+            "createSql": "CREATE UNIQUE INDEX IF NOT EXISTS `index_op_log_clientId_clientSeq` ON `${TABLE_NAME}` (`clientId`, `clientSeq`)"
+          },
+          {
+            "name": "index_op_log_synced",
+            "unique": false,
+            "columnNames": [
+              "synced"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_op_log_synced` ON `${TABLE_NAME}` (`synced`)"
+          }
+        ]
+      }
+    ],
+    "setupQueries": [
+      "CREATE TABLE IF NOT EXISTS room_master_table (id INTEGER PRIMARY KEY,identity_hash TEXT)",
+      "INSERT OR REPLACE INTO room_master_table (id,identity_hash) VALUES(42, 'c5e70cf816f82a65da0a30d8315b70e8')"
+    ]
+  }
+}
--- a/android/app/src/androidTest/java/com/example/mitbringsl/ui/main/MainScreenTest.kt
+++ b/android/app/src/androidTest/java/com/example/mitbringsl/ui/main/MainScreenTest.kt
@ -0,0 +1,26 @@
+package com.example.mitbringsl.ui.main
+
+import androidx.activity.ComponentActivity
+import androidx.compose.ui.test.junit4.createAndroidComposeRule
+import androidx.compose.ui.test.onNodeWithText
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+
+/** UI tests for [com.example.mitbringsl.ui.main.MainScreen]. */
+class MainScreenTest {
+
+  @get:Rule val composeTestRule = createAndroidComposeRule<ComponentActivity>()
+
+  @Before
+  fun setup() {
+    composeTestRule.setContent { MainScreen(FAKE_DATA) }
+  }
+
+  @Test
+  fun firstItem_exists() {
+    FAKE_DATA.forEach { composeTestRule.onNodeWithText(it).assertExists() }
+  }
+}
+
+private val FAKE_DATA = listOf("Sample1", "Sample2", "Sample3")
--- a/android/app/src/main/AndroidManifest.xml
+++ b/android/app/src/main/AndroidManifest.xml
@ -0,0 +1,28 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <uses-permission android:name="android.permission.INTERNET" />
+
+    <application
+        android:name=".MitbringslApp"
+        android:allowBackup="true"
+        android:dataExtractionRules="@xml/data_extraction_rules"
+        android:fullBackupContent="@xml/backup_rules"
+        android:icon="@mipmap/ic_launcher"
+        android:label="@string/app_name"
+        android:roundIcon="@mipmap/ic_launcher_round"
+        android:supportsRtl="true"
+        android:windowSoftInputMode="adjustResize"
+        android:theme="@style/Theme.Mitbringsl">
+
+        <activity
+            android:name=".MainActivity"
+            android:exported="true">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+    </application>
+
+</manifest>
--- a/android/app/src/main/java/com/example/mitbringsl/MainActivity.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/MainActivity.kt
@ -0,0 +1,26 @@
+package com.example.mitbringsl
+
+import android.os.Bundle
+import androidx.activity.ComponentActivity
+import androidx.activity.compose.setContent
+import androidx.activity.enableEdgeToEdge
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.ui.Modifier
+import com.example.mitbringsl.theme.MitbringslTheme
+
+import dagger.hilt.android.AndroidEntryPoint
+
+@AndroidEntryPoint
+class MainActivity : ComponentActivity() {
+
+  override fun onCreate(savedInstanceState: Bundle?) {
+    super.onCreate(savedInstanceState)
+
+    enableEdgeToEdge()
+    setContent {
+      MitbringslTheme { Surface(modifier = Modifier.fillMaxSize(), color = MaterialTheme.colorScheme.background) { MainNavigation() } }
+    }
+  }
+}
--- a/android/app/src/main/java/com/example/mitbringsl/MitbringslApp.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/MitbringslApp.kt
@ -0,0 +1,18 @@
+package com.example.mitbringsl
+
+import android.app.Application
+import androidx.hilt.work.HiltWorkerFactory
+import androidx.work.Configuration
+import dagger.hilt.android.HiltAndroidApp
+import javax.inject.Inject
+
+@HiltAndroidApp
+class MitbringslApp : Application(), Configuration.Provider {
+
+    @Inject lateinit var workerFactory: HiltWorkerFactory
+
+    override val workManagerConfiguration: Configuration
+        get() = Configuration.Builder()
+            .setWorkerFactory(workerFactory)
+            .build()
+}
--- a/android/app/src/main/java/com/example/mitbringsl/Navigation.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/Navigation.kt
@ -0,0 +1,27 @@
+package com.example.mitbringsl
+
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.safeDrawingPadding
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import androidx.navigation3.runtime.entryProvider
+import androidx.navigation3.runtime.rememberNavBackStack
+import androidx.navigation3.ui.NavDisplay
+import com.example.mitbringsl.ui.main.MainScreen
+
+@Composable
+fun MainNavigation() {
+  val backStack = rememberNavBackStack(Main)
+
+  NavDisplay(
+    backStack = backStack,
+    onBack = { backStack.removeLastOrNull() },
+    entryProvider =
+      entryProvider {
+        entry<Main> {
+          MainScreen(onItemClick = { navKey -> backStack.add(navKey) }, modifier = Modifier.safeDrawingPadding().padding(16.dp))
+        }
+      },
+  )
+}
--- a/android/app/src/main/java/com/example/mitbringsl/NavigationKeys.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/NavigationKeys.kt
@ -0,0 +1,6 @@
+package com.example.mitbringsl
+
+import androidx.navigation3.runtime.NavKey
+import kotlinx.serialization.Serializable
+
+@Serializable data object Main : NavKey
--- a/android/app/src/main/java/com/example/mitbringsl/data/DataRepository.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/data/DataRepository.kt
@ -0,0 +1,32 @@
+package com.example.mitbringsl.data
+
+import com.example.mitbringsl.data.local.dao.ListDao
+import com.example.mitbringsl.data.local.entity.ListEntity
+import kotlinx.coroutines.flow.Flow
+import javax.inject.Inject
+import javax.inject.Singleton
+
+/**
+ * Repository interface for shopping lists.
+ * Phase D stub – only observes local Room data.
+ * Phase E will add the full sync logic (push outbox + pull cursor).
+ */
+interface ListRepository {
+    fun observeLists(ownerId: String): Flow<List<ListEntity>>
+    suspend fun createList(name: String, ownerId: String): ListEntity
+}
+
+@Singleton
+class DefaultListRepository @Inject constructor(
+    private val listDao: ListDao,
+) : ListRepository {
+
+    override fun observeLists(ownerId: String): Flow<List<ListEntity>> =
+        listDao.observeLists(ownerId)
+
+    override suspend fun createList(name: String, ownerId: String): ListEntity {
+        val entity = ListEntity(name = name, ownerId = ownerId)
+        listDao.upsert(entity)
+        return entity
+    }
+}
--- a/android/app/src/main/java/com/example/mitbringsl/data/local/AppDatabase.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/data/local/AppDatabase.kt
@ -0,0 +1,29 @@
+package com.example.mitbringsl.data.local
+
+import androidx.room.Database
+import androidx.room.RoomDatabase
+import com.example.mitbringsl.data.local.dao.ItemDao
+import com.example.mitbringsl.data.local.dao.ListDao
+import com.example.mitbringsl.data.local.dao.OpLogDao
+import com.example.mitbringsl.data.local.entity.ItemEntity
+import com.example.mitbringsl.data.local.entity.ListEntity
+import com.example.mitbringsl.data.local.entity.OpLogEntity
+
+@Database(
+    entities = [
+        ListEntity::class,
+        ItemEntity::class,
+        OpLogEntity::class,
+    ],
+    version = 1,
+    exportSchema = true,
+)
+abstract class AppDatabase : RoomDatabase() {
+    abstract fun listDao(): ListDao
+    abstract fun itemDao(): ItemDao
+    abstract fun opLogDao(): OpLogDao
+
+    companion object {
+        const val DATABASE_NAME = "mitbringsl.db"
+    }
+}
--- a/android/app/src/main/java/com/example/mitbringsl/data/local/dao/ItemDao.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/data/local/dao/ItemDao.kt
@ -0,0 +1,52 @@
+package com.example.mitbringsl.data.local.dao
+
+import androidx.room.*
+import com.example.mitbringsl.data.local.entity.ItemEntity
+import kotlinx.coroutines.flow.Flow
+
+@Dao
+interface ItemDao {
+
+    /** Observe all non-deleted items for a list, ordered by sort_order then creation time. */
+    @Query("""
+        SELECT * FROM items
+        WHERE listId = :listId AND deletedAt IS NULL
+        ORDER BY sortOrder ASC, createdAt ASC
+    """)
+    fun observeItems(listId: String): Flow<List<ItemEntity>>
+
+    @Upsert
+    suspend fun upsert(item: ItemEntity)
+
+    @Upsert
+    suspend fun upsertAll(items: List<ItemEntity>)
+
+    /**
+     * LWW upsert – only updates mutable fields when incoming hlc_ts is greater.
+     * The tombstone (deletedAt) is also applied through LWW.
+     */
+    @Query("""
+        INSERT INTO items (id, listId, name, quantity, checked, sortOrder,
+                           createdAt, updatedAt, deletedAt, hlcTs, clientId, checkedAt)
+        VALUES (:id, :listId, :name, :quantity, :checked, :sortOrder,
+                :createdAt, :updatedAt, :deletedAt, :hlcTs, :clientId, :checkedAt)
+        ON CONFLICT(id) DO UPDATE SET
+          name      = CASE WHEN :hlcTs > hlcTs THEN :name      ELSE name      END,
+          quantity  = CASE WHEN :hlcTs > hlcTs THEN :quantity  ELSE quantity  END,
+          checked   = CASE WHEN :hlcTs > hlcTs THEN :checked   ELSE checked   END,
+          sortOrder = CASE WHEN :hlcTs > hlcTs THEN :sortOrder ELSE sortOrder END,
+          updatedAt = CASE WHEN :hlcTs > hlcTs THEN :updatedAt ELSE updatedAt END,
+          deletedAt = CASE WHEN :hlcTs > hlcTs THEN :deletedAt ELSE deletedAt END,
+          checkedAt = CASE WHEN :hlcTs > hlcTs THEN :checkedAt ELSE checkedAt END,
+          hlcTs     = CASE WHEN :hlcTs > hlcTs THEN :hlcTs     ELSE hlcTs     END
+    """)
+    suspend fun upsertLww(
+        id: String, listId: String, name: String, quantity: String?,
+        checked: Boolean, sortOrder: Int?,
+        createdAt: Long, updatedAt: Long, deletedAt: Long?,
+        hlcTs: Long, clientId: String?, checkedAt: Long?,
+    )
+
+    @Query("SELECT * FROM items WHERE id = :itemId LIMIT 1")
+    suspend fun getItem(itemId: String): ItemEntity?
+}
--- a/android/app/src/main/java/com/example/mitbringsl/data/local/dao/ListDao.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/data/local/dao/ListDao.kt
@ -0,0 +1,51 @@
+package com.example.mitbringsl.data.local.dao
+
+import androidx.room.*
+import com.example.mitbringsl.data.local.entity.ListEntity
+import kotlinx.coroutines.flow.Flow
+
+@Dao
+interface ListDao {
+
+    /** Observe all non-deleted lists for a given owner, newest first. */
+    @Query("SELECT * FROM lists WHERE ownerId = :ownerId AND deletedAt IS NULL ORDER BY updatedAt DESC")
+    fun observeLists(ownerId: String): Flow<List<ListEntity>>
+
+    /** One-shot lookup of a single list. */
+    @Query("SELECT * FROM lists WHERE id = :listId AND deletedAt IS NULL LIMIT 1")
+    suspend fun getList(listId: String): ListEntity?
+
+    /**
+     * Upsert a list.
+     * On conflict (same primary key) the row is replaced so that fresh data
+     * from the server always wins in the initial seed / full-sync path.
+     * For LWW conflict resolution during incremental sync, see [upsertLww].
+     */
+    @Upsert
+    suspend fun upsert(list: ListEntity)
+
+    @Upsert
+    suspend fun upsertAll(lists: List<ListEntity>)
+
+    /**
+     * LWW upsert: only update if the incoming hlc_ts is strictly greater than
+     * the stored one (Last-Write-Wins register).
+     */
+    @Query("""
+        INSERT INTO lists (id, name, ownerId, createdAt, updatedAt, deletedAt, hlcTs)
+        VALUES (:id, :name, :ownerId, :createdAt, :updatedAt, :deletedAt, :hlcTs)
+        ON CONFLICT(id) DO UPDATE SET
+          name      = CASE WHEN :hlcTs > hlcTs THEN :name      ELSE name      END,
+          updatedAt = CASE WHEN :hlcTs > hlcTs THEN :updatedAt ELSE updatedAt END,
+          deletedAt = CASE WHEN :hlcTs > hlcTs THEN :deletedAt ELSE deletedAt END,
+          hlcTs     = CASE WHEN :hlcTs > hlcTs THEN :hlcTs     ELSE hlcTs     END
+    """)
+    suspend fun upsertLww(
+        id: String, name: String, ownerId: String,
+        createdAt: Long, updatedAt: Long,
+        deletedAt: Long?, hlcTs: Long,
+    )
+
+    @Query("SELECT COUNT(*) FROM lists WHERE ownerId = :ownerId AND deletedAt IS NULL")
+    suspend fun count(ownerId: String): Int
+}
--- a/android/app/src/main/java/com/example/mitbringsl/data/local/dao/OpLogDao.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/data/local/dao/OpLogDao.kt
@ -0,0 +1,43 @@
+package com.example.mitbringsl.data.local.dao
+
+import androidx.room.*
+import com.example.mitbringsl.data.local.entity.OpLogEntity
+import kotlinx.coroutines.flow.Flow
+
+@Dao
+interface OpLogDao {
+
+    /** All unsynced ops ordered by creation time (oldest first for FIFO drain). */
+    @Query("SELECT * FROM op_log WHERE synced = 0 ORDER BY createdAt ASC, localId ASC")
+    fun observeUnsynced(): Flow<List<OpLogEntity>>
+
+    @Query("SELECT * FROM op_log WHERE synced = 0 ORDER BY createdAt ASC, localId ASC")
+    suspend fun getUnsynced(): List<OpLogEntity>
+
+    /** Unsynced ops for a specific list. */
+    @Query("SELECT * FROM op_log WHERE listId = :listId AND synced = 0 ORDER BY createdAt ASC")
+    suspend fun getUnsyncedForList(listId: String): List<OpLogEntity>
+
+    @Insert(onConflict = OnConflictStrategy.IGNORE)
+    suspend fun insert(op: OpLogEntity): Long
+
+    /** Mark an op as synced and store the server-assigned seq. */
+    @Query("UPDATE op_log SET synced = 1, serverSeq = :serverSeq WHERE localId = :localId")
+    suspend fun markSynced(localId: Long, serverSeq: Long)
+
+    /** Mark multiple ops synced at once (by localId). */
+    @Transaction
+    suspend fun markAllSynced(results: Map<Long, Long>) {
+        results.forEach { (localId, serverSeq) -> markSynced(localId, serverSeq) }
+    }
+
+    @Query("DELETE FROM op_log WHERE synced = 1 AND createdAt < :olderThanMs")
+    suspend fun deleteOldSynced(olderThanMs: Long)
+
+    @Query("SELECT COUNT(*) FROM op_log WHERE synced = 0")
+    fun observeUnsyncedCount(): Flow<Int>
+
+    /** Highest server seq we have stored locally for a given list (used as pull cursor). */
+    @Query("SELECT MAX(serverSeq) FROM op_log WHERE listId = :listId AND synced = 1")
+    suspend fun maxServerSeq(listId: String): Long?
+}
--- a/android/app/src/main/java/com/example/mitbringsl/data/local/entity/ItemEntity.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/data/local/entity/ItemEntity.kt
@ -0,0 +1,39 @@
+package com.example.mitbringsl.data.local.entity
+
+import androidx.room.Entity
+import androidx.room.ForeignKey
+import androidx.room.Index
+import androidx.room.PrimaryKey
+
+/**
+ * Local projection of a shopping list item.
+ * Source of truth flows from [OpLogEntity] via the sync engine.
+ */
+@Entity(
+    tableName = "items",
+    foreignKeys = [
+        ForeignKey(
+            entity = ListEntity::class,
+            parentColumns = ["id"],
+            childColumns = ["listId"],
+            onDelete = ForeignKey.CASCADE,
+        )
+    ],
+    indices = [Index("listId"), Index("deletedAt")]
+)
+data class ItemEntity(
+    @PrimaryKey val id: String,
+    val listId: String,
+    val name: String,
+    val quantity: String? = null,
+    val checked: Boolean = false,
+    val sortOrder: Int? = null,
+    val createdAt: Long = System.currentTimeMillis(),
+    val updatedAt: Long = System.currentTimeMillis(),
+    /** Tombstone – null means the item is alive. */
+    val deletedAt: Long? = null,
+    val hlcTs: Long = 0L,
+    /** UUID of the client that created this item. */
+    val clientId: String? = null,
+    val checkedAt: Long? = null,
+)
--- a/android/app/src/main/java/com/example/mitbringsl/data/local/entity/ListEntity.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/data/local/entity/ListEntity.kt
@ -0,0 +1,26 @@
+package com.example.mitbringsl.data.local.entity
+
+import androidx.room.Entity
+import androidx.room.Index
+import androidx.room.PrimaryKey
+import java.util.UUID
+
+/**
+ * Local projection of a shopping list.
+ * Written by the sync engine when ops arrive from the server.
+ * [ownerId] is the authenticated user's ID (UUID string).
+ */
+@Entity(
+    tableName = "lists",
+    indices = [Index("ownerId"), Index("deletedAt")]
+)
+data class ListEntity(
+    @PrimaryKey val id: String = UUID.randomUUID().toString(),
+    val name: String,
+    val ownerId: String,
+    val createdAt: Long = System.currentTimeMillis(),
+    val updatedAt: Long = System.currentTimeMillis(),
+    val deletedAt: Long? = null,
+    /** Hybrid Logical Clock timestamp – used for LWW conflict resolution. */
+    val hlcTs: Long = 0L,
+)
--- a/android/app/src/main/java/com/example/mitbringsl/data/local/entity/OpLogEntity.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/data/local/entity/OpLogEntity.kt
@ -0,0 +1,42 @@
+package com.example.mitbringsl.data.local.entity
+
+import androidx.room.Entity
+import androidx.room.Index
+import androidx.room.PrimaryKey
+
+/**
+ * Client-side op_log – the outbox for unsynced operations.
+ *
+ * Each row is a pending operation that has not yet been acknowledged by the
+ * server. The sync engine drains this table by pushing ops via
+ * POST /api/lists/{id}/ops and removes rows on success.
+ *
+ * [clientSeq] is a monotonically-increasing counter scoped to [clientId].
+ * Together they form the idempotency key used by the server.
+ */
+@Entity(
+    tableName = "op_log",
+    indices = [
+        Index("listId"),
+        Index(value = ["clientId", "clientSeq"], unique = true),
+        Index("synced"),
+    ]
+)
+data class OpLogEntity(
+    @PrimaryKey(autoGenerate = true) val localId: Long = 0,
+    val listId: String,
+    /** UUID of this device installation – stable, generated once. */
+    val clientId: String,
+    val clientSeq: Long,
+    /** One of: list_create, list_rename, list_delete, item_add, item_update, item_remove. */
+    val opType: String,
+    val targetId: String,
+    /** JSON payload, e.g. {"name":"Milch","quantity":"1L"}. */
+    val payload: String = "{}",
+    /** Client-generated HLC timestamp. */
+    val hlcTs: Long,
+    val createdAt: Long = System.currentTimeMillis(),
+    /** Set to the server-assigned seq once the op has been acknowledged. */
+    val serverSeq: Long? = null,
+    val synced: Boolean = false,
+)
--- a/android/app/src/main/java/com/example/mitbringsl/data/remote/api/AuthInterceptor.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/data/remote/api/AuthInterceptor.kt
@ -0,0 +1,25 @@
+package com.example.mitbringsl.data.remote.api
+
+import okhttp3.Interceptor
+import okhttp3.Response
+
+/**
+ * OkHttp interceptor that injects the session Bearer token into every request.
+ *
+ * [tokenProvider] is a lambda so the interceptor always reads the most recent
+ * token without needing to be recreated after login.
+ */
+class AuthInterceptor(private val tokenProvider: () -> String?) : Interceptor {
+
+    override fun intercept(chain: Interceptor.Chain): Response {
+        val token = tokenProvider()
+        val request = if (token.isNullOrBlank()) {
+            chain.request()
+        } else {
+            chain.request().newBuilder()
+                .header("Authorization", "Bearer $token")
+                .build()
+        }
+        return chain.proceed(request)
+    }
+}
--- a/android/app/src/main/java/com/example/mitbringsl/data/remote/api/MitbringslApi.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/data/remote/api/MitbringslApi.kt
@ -0,0 +1,59 @@
+package com.example.mitbringsl.data.remote.api
+
+import com.example.mitbringsl.data.remote.dto.*
+import retrofit2.Response
+import retrofit2.http.*
+
+/**
+ * Retrofit API interface matching the mitbringsl backend.
+ *
+ * Authentication: every authenticated call must include
+ *   Authorization: Bearer <session-token>
+ * This is injected by the AuthInterceptor in the OkHttp client.
+ */
+interface MitbringslApi {
+
+    // --- Auth ---------------------------------------------------------------
+
+    @POST("auth/register")
+    suspend fun register(@Body body: RegisterRequestDto): Response<AuthResponseDto>
+
+    @POST("auth/login")
+    suspend fun login(@Body body: LoginRequestDto): Response<AuthResponseDto>
+
+    @POST("auth/oidc")
+    suspend fun loginOidc(@Body body: OidcRequestDto): Response<AuthResponseDto>
+
+    @POST("auth/logout")
+    suspend fun logout(): Response<Unit>
+
+    // --- Lists --------------------------------------------------------------
+
+    @GET("api/lists")
+    suspend fun getLists(): Response<ListsResponseDto>
+
+    @POST("api/lists")
+    suspend fun createList(@Body body: CreateListRequestDto): Response<ListDto>
+
+    @GET("api/lists/{id}")
+    suspend fun getList(@Path("id") listId: String): Response<ListDetailDto>
+
+    // --- Ops ----------------------------------------------------------------
+
+    @POST("api/lists/{id}/ops")
+    suspend fun pushOps(
+        @Path("id") listId: String,
+        @Body body: PushRequestDto,
+    ): Response<PushResponseDto>
+
+    @GET("api/lists/{id}/ops")
+    suspend fun pullOps(
+        @Path("id") listId: String,
+        @Query("since") since: Long,
+    ): Response<PullResponseDto>
+
+    // --- Suggestions --------------------------------------------------------
+
+    @GET("api/suggestions")
+    suspend fun getSuggestions(@Query("q") query: String): Response<SuggestionsResponseDto>
+}
--- a/android/app/src/main/java/com/example/mitbringsl/data/remote/dto/Dtos.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/data/remote/dto/Dtos.kt
@ -0,0 +1,138 @@
+package com.example.mitbringsl.data.remote.dto
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+import kotlinx.serialization.json.JsonObject
+
+// ---------------------------------------------------------------------------
+// Auth
+// ---------------------------------------------------------------------------
+
+@Serializable
+data class RegisterRequestDto(
+    val email: String,
+    val password: String,
+    @SerialName("display_name") val displayName: String = "",
+)
+
+@Serializable
+data class LoginRequestDto(
+    val email: String,
+    val password: String,
+)
+
+@Serializable
+data class OidcRequestDto(
+    val provider: String,
+    @SerialName("id_token") val idToken: String,
+)
+
+@Serializable
+data class AuthResponseDto(
+    val token: String,
+    @SerialName("expires_at") val expiresAt: String,
+    val user: UserDto,
+)
+
+@Serializable
+data class UserDto(
+    val id: String,
+    val email: String,
+    @SerialName("display_name") val displayName: String = "",
+)
+
+// ---------------------------------------------------------------------------
+// Lists
+// ---------------------------------------------------------------------------
+
+@Serializable
+data class CreateListRequestDto(val name: String)
+
+@Serializable
+data class ListDto(
+    val id: String,
+    val name: String,
+    @SerialName("updated_at") val updatedAt: String,
+    @SerialName("hlc_ts") val hlcTs: Long,
+)
+
+@Serializable
+data class ListsResponseDto(val lists: List<ListDto>)
+
+@Serializable
+data class ListDetailDto(
+    val id: String,
+    val name: String,
+    @SerialName("updated_at") val updatedAt: String,
+    @SerialName("hlc_ts") val hlcTs: Long,
+    val items: List<ItemDto>,
+)
+
+@Serializable
+data class ItemDto(
+    val id: String,
+    @SerialName("list_id") val listId: String,
+    val name: String,
+    val quantity: String? = null,
+    val checked: Boolean = false,
+    @SerialName("sort_order") val sortOrder: Int? = null,
+    @SerialName("created_at") val createdAt: String,
+    @SerialName("updated_at") val updatedAt: String,
+    @SerialName("hlc_ts") val hlcTs: Long,
+    @SerialName("client_id") val clientId: String? = null,
+    @SerialName("checked_at") val checkedAt: String? = null,
+)
+
+// ---------------------------------------------------------------------------
+// Ops (Push / Pull)
+// ---------------------------------------------------------------------------
+
+@Serializable
+data class PushRequestDto(
+    @SerialName("client_id") val clientId: String,
+    val ops: List<IncomingOpDto>,
+)
+
+@Serializable
+data class IncomingOpDto(
+    @SerialName("client_seq") val clientSeq: Long,
+    @SerialName("op_type") val opType: String,
+    @SerialName("target_id") val targetId: String,
+    @SerialName("hlc_ts") val hlcTs: Long,
+    val payload: JsonObject,
+)
+
+@Serializable
+data class PushResponseDto(val results: List<OpResultDto>)
+
+@Serializable
+data class OpResultDto(
+    @SerialName("client_seq") val clientSeq: Long,
+    val seq: Long,
+    @SerialName("hlc_ts") val hlcTs: Long,
+)
+
+@Serializable
+data class PullResponseDto(
+    val ops: List<ServerOpDto>,
+    @SerialName("has_more") val hasMore: Boolean,
+)
+
+@Serializable
+data class ServerOpDto(
+    val seq: Long,
+    @SerialName("client_id") val clientId: String,
+    @SerialName("op_type") val opType: String,
+    @SerialName("target_id") val targetId: String,
+    val payload: JsonObject,
+    @SerialName("client_seq") val clientSeq: Long,
+    @SerialName("hlc_ts") val hlcTs: Long,
+    @SerialName("created_at") val createdAt: String,
+)
+
+// ---------------------------------------------------------------------------
+// Suggestions
+// ---------------------------------------------------------------------------
+
+@Serializable
+data class SuggestionsResponseDto(val suggestions: List<String>)
--- a/android/app/src/main/java/com/example/mitbringsl/di/DatabaseModule.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/di/DatabaseModule.kt
@ -0,0 +1,30 @@
+package com.example.mitbringsl.di
+
+import android.content.Context
+import androidx.room.Room
+import com.example.mitbringsl.data.local.AppDatabase
+import com.example.mitbringsl.data.local.dao.ItemDao
+import com.example.mitbringsl.data.local.dao.ListDao
+import com.example.mitbringsl.data.local.dao.OpLogDao
+import dagger.Module
+import dagger.Provides
+import dagger.hilt.InstallIn
+import dagger.hilt.android.qualifiers.ApplicationContext
+import dagger.hilt.components.SingletonComponent
+import javax.inject.Singleton
+
+@Module
+@InstallIn(SingletonComponent::class)
+object DatabaseModule {
+
+    @Provides
+    @Singleton
+    fun provideDatabase(@ApplicationContext context: Context): AppDatabase =
+        Room.databaseBuilder(context, AppDatabase::class.java, AppDatabase.DATABASE_NAME)
+            .fallbackToDestructiveMigration(dropAllTables = false)
+            .build()
+
+    @Provides fun provideListDao(db: AppDatabase): ListDao = db.listDao()
+    @Provides fun provideItemDao(db: AppDatabase): ItemDao = db.itemDao()
+    @Provides fun provideOpLogDao(db: AppDatabase): OpLogDao = db.opLogDao()
+}
--- a/android/app/src/main/java/com/example/mitbringsl/di/NetworkModule.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/di/NetworkModule.kt
@ -0,0 +1,73 @@
+package com.example.mitbringsl.di
+
+import android.content.Context
+import com.example.mitbringsl.BuildConfig
+import com.example.mitbringsl.data.remote.api.AuthInterceptor
+import com.example.mitbringsl.data.remote.api.MitbringslApi
+import dagger.Module
+import dagger.Provides
+import dagger.hilt.InstallIn
+import dagger.hilt.android.qualifiers.ApplicationContext
+import dagger.hilt.components.SingletonComponent
+import kotlinx.serialization.json.Json
+import okhttp3.MediaType.Companion.toMediaType
+import okhttp3.OkHttpClient
+import okhttp3.logging.HttpLoggingInterceptor
+import retrofit2.Retrofit
+import retrofit2.converter.kotlinx.serialization.asConverterFactory
+import javax.inject.Singleton
+
+@Module
+@InstallIn(SingletonComponent::class)
+object NetworkModule {
+
+    /**
+     * Lax JSON decoder: ignores unknown keys so the app doesn't crash when the
+     * backend adds new fields, and handles missing optional fields gracefully.
+     */
+    @Provides
+    @Singleton
+    fun provideJson(): Json = Json {
+        ignoreUnknownKeys = true
+        isLenient = true
+        coerceInputValues = true
+    }
+
+    @Provides
+    @Singleton
+    fun provideTokenProvider(@ApplicationContext context: Context): () -> String? = {
+        // Read token from SharedPreferences (written after login).
+        context.getSharedPreferences("session", Context.MODE_PRIVATE)
+            .getString("token", null)
+    }
+
+    @Provides
+    @Singleton
+    fun provideOkHttpClient(tokenProvider: () -> String?): OkHttpClient {
+        val logging = HttpLoggingInterceptor().apply {
+            level = if (BuildConfig.DEBUG) {
+                HttpLoggingInterceptor.Level.BODY
+            } else {
+                HttpLoggingInterceptor.Level.NONE
+            }
+        }
+        return OkHttpClient.Builder()
+            .addInterceptor(AuthInterceptor(tokenProvider))
+            .addInterceptor(logging)
+            .build()
+    }
+
+    @Provides
+    @Singleton
+    fun provideRetrofit(client: OkHttpClient, json: Json): Retrofit =
+        Retrofit.Builder()
+            .baseUrl(BuildConfig.BASE_URL)
+            .client(client)
+            .addConverterFactory(json.asConverterFactory("application/json; charset=UTF-8".toMediaType()))
+            .build()
+
+    @Provides
+    @Singleton
+    fun provideMitbringslApi(retrofit: Retrofit): MitbringslApi =
+        retrofit.create(MitbringslApi::class.java)
+}
--- a/android/app/src/main/java/com/example/mitbringsl/di/RepositoryModule.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/di/RepositoryModule.kt
@ -0,0 +1,18 @@
+package com.example.mitbringsl.di
+
+import com.example.mitbringsl.data.DefaultListRepository
+import com.example.mitbringsl.data.ListRepository
+import dagger.Binds
+import dagger.Module
+import dagger.hilt.InstallIn
+import dagger.hilt.components.SingletonComponent
+import javax.inject.Singleton
+
+@Module
+@InstallIn(SingletonComponent::class)
+abstract class RepositoryModule {
+
+    @Binds
+    @Singleton
+    abstract fun bindListRepository(impl: DefaultListRepository): ListRepository
+}
--- a/android/app/src/main/java/com/example/mitbringsl/theme/Color.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/theme/Color.kt
@ -0,0 +1,11 @@
+package com.example.mitbringsl.theme
+
+import androidx.compose.ui.graphics.Color
+
+val Purple80 = Color(0xFFD0BCFF)
+val PurpleGrey80 = Color(0xFFCCC2DC)
+val Pink80 = Color(0xFFEFB8C8)
+
+val Purple40 = Color(0xFF6650a4)
+val PurpleGrey40 = Color(0xFF625b71)
+val Pink40 = Color(0xFF7D5260)
--- a/android/app/src/main/java/com/example/mitbringsl/theme/Theme.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/theme/Theme.kt
@ -0,0 +1,50 @@
+package com.example.mitbringsl.theme
+
+import android.os.Build
+import androidx.compose.foundation.isSystemInDarkTheme
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.darkColorScheme
+import androidx.compose.material3.dynamicDarkColorScheme
+import androidx.compose.material3.dynamicLightColorScheme
+import androidx.compose.material3.lightColorScheme
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.platform.LocalContext
+
+private val DarkColorScheme = darkColorScheme(primary = Purple80, secondary = PurpleGrey80, tertiary = Pink80)
+
+private val LightColorScheme =
+  lightColorScheme(
+    primary = Purple40,
+    secondary = PurpleGrey40,
+    tertiary = Pink40,
+
+    /* Other default colors to override
+    background = Color(0xFFFFFBFE),
+    surface = Color(0xFFFFFBFE),
+    onPrimary = Color.White,
+    onSecondary = Color.White,
+    onTertiary = Color.White,
+    onBackground = Color(0xFF1C1B1F),
+    onSurface = Color(0xFF1C1B1F),
+    */
+  )
+
+@Composable
+fun MitbringslTheme(
+  darkTheme: Boolean = isSystemInDarkTheme(),
+  // Dynamic color is available on Android 12+
+  dynamicColor: Boolean = true,
+  content: @Composable () -> Unit,
+) {
+  val colorScheme =
+    when {
+      dynamicColor && Build.VERSION.SDK_INT >= Build.VERSION_CODES.S -> {
+        val context = LocalContext.current
+        if (darkTheme) dynamicDarkColorScheme(context) else dynamicLightColorScheme(context)
+      }
+      darkTheme -> DarkColorScheme
+      else -> LightColorScheme
+    }
+
+  MaterialTheme(colorScheme = colorScheme, typography = Typography, content = content)
+}
--- a/android/app/src/main/java/com/example/mitbringsl/theme/Type.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/theme/Type.kt
@ -0,0 +1,36 @@
+package com.example.mitbringsl.theme
+
+import androidx.compose.material3.Typography
+import androidx.compose.ui.text.TextStyle
+import androidx.compose.ui.text.font.FontFamily
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.unit.sp
+
+// Set of Material typography styles to start with
+val Typography =
+  Typography(
+    bodyLarge =
+      TextStyle(
+        fontFamily = FontFamily.Default,
+        fontWeight = FontWeight.Normal,
+        fontSize = 16.sp,
+        lineHeight = 24.sp,
+        letterSpacing = 0.5.sp,
+      )
+    /* Other default text styles to override
+    titleLarge = TextStyle(
+        fontFamily = FontFamily.Default,
+        fontWeight = FontWeight.Normal,
+        fontSize = 22.sp,
+        lineHeight = 28.sp,
+        letterSpacing = 0.sp
+    ),
+    labelSmall = TextStyle(
+        fontFamily = FontFamily.Default,
+        fontWeight = FontWeight.Medium,
+        fontSize = 11.sp,
+        lineHeight = 16.sp,
+        letterSpacing = 0.5.sp
+    )
+    */
+  )
--- a/android/app/src/main/java/com/example/mitbringsl/ui/main/MainScreen.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/ui/main/MainScreen.kt
@ -0,0 +1,35 @@
+package com.example.mitbringsl.ui.main
+
+import androidx.compose.foundation.layout.Column
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.hilt.navigation.compose.hiltViewModel
+import androidx.navigation3.runtime.NavKey
+import com.example.mitbringsl.theme.MitbringslTheme
+
+@Composable
+fun MainScreen(
+  onItemClick: (NavKey) -> Unit,
+  modifier: Modifier = Modifier,
+  viewModel: MainScreenViewModel = hiltViewModel(),
+) {
+  MainScreen(data = listOf("Mitbringsl App Initialized"), modifier = modifier)
+}
+
+@Composable
+internal fun MainScreen(data: List<String>, modifier: Modifier = Modifier) {
+  Column(modifier) { data.forEach { Greeting(it) } }
+}
+
+@Composable
+fun Greeting(name: String, modifier: Modifier = Modifier) {
+  Text(text = "$name", modifier = modifier)
+}
+
+@Preview(showBackground = true)
+@Composable
+fun MainScreenPreview() {
+  MitbringslTheme { MainScreen(listOf("Mitbringsl App Initialized")) }
+}
--- a/android/app/src/main/java/com/example/mitbringsl/ui/main/MainScreenViewModel.kt
+++ b/android/app/src/main/java/com/example/mitbringsl/ui/main/MainScreenViewModel.kt
@ -0,0 +1,18 @@
+package com.example.mitbringsl.ui.main
+
+import androidx.lifecycle.ViewModel
+import dagger.hilt.android.lifecycle.HiltViewModel
+import javax.inject.Inject
+
+/**
+ * Placeholder ViewModel for the main screen.
+ * Will be replaced in Phase E with the full ListsViewModel backed by Room.
+ */
+@HiltViewModel
+class MainScreenViewModel @Inject constructor() : ViewModel()
+
+sealed interface MainScreenUiState {
+    object Loading : MainScreenUiState
+    data class Error(val throwable: Throwable) : MainScreenUiState
+    data class Success(val data: List<String>) : MainScreenUiState
+}
--- a/android/app/src/main/res/drawable/ic_launcher_background.xml
+++ b/android/app/src/main/res/drawable/ic_launcher_background.xml
@ -0,0 +1,170 @@
+<?xml version="1.0" encoding="utf-8"?>
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path
+        android:fillColor="#3DDC84"
+        android:pathData="M0,0h108v108h-108z" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M9,0L9,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,0L19,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M29,0L29,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M39,0L39,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M49,0L49,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M59,0L59,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M69,0L69,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M79,0L79,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M89,0L89,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M99,0L99,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,9L108,9"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,19L108,19"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,29L108,29"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,39L108,39"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,49L108,49"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,59L108,59"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,69L108,69"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,79L108,79"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,89L108,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,99L108,99"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,29L89,29"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,39L89,39"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,49L89,49"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,59L89,59"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,69L89,69"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,79L89,79"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M29,19L29,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M39,19L39,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M49,19L49,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M59,19L59,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M69,19L69,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M79,19L79,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+</vector>
--- a/android/app/src/main/res/drawable/ic_launcher_foreground.xml
+++ b/android/app/src/main/res/drawable/ic_launcher_foreground.xml
@ -0,0 +1,30 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:aapt="http://schemas.android.com/aapt"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path android:pathData="M31,63.928c0,0 6.4,-11 12.1,-13.1c7.2,-2.6 26,-1.4 26,-1.4l38.1,38.1L107,108.928l-32,-1L31,63.928z">
+        <aapt:attr name="android:fillColor">
+            <gradient
+                android:endX="85.84757"
+                android:endY="92.4963"
+                android:startX="42.9492"
+                android:startY="49.59793"
+                android:type="linear">
+                <item
+                    android:color="#44000000"
+                    android:offset="0.0" />
+                <item
+                    android:color="#00000000"
+                    android:offset="1.0" />
+            </gradient>
+        </aapt:attr>
+    </path>
+    <path
+        android:fillColor="#FFFFFF"
+        android:fillType="nonZero"
+        android:pathData="M65.3,45.828l3.8,-6.6c0.2,-0.4 0.1,-0.9 -0.3,-1.1c-0.4,-0.2 -0.9,-0.1 -1.1,0.3l-3.9,6.7c-6.3,-2.8 -13.4,-2.8 -19.7,0l-3.9,-6.7c-0.2,-0.4 -0.7,-0.5 -1.1,-0.3C38.8,38.328 38.7,38.828 38.9,39.228l3.8,6.6C36.2,49.428 31.7,56.028 31,63.928h46C76.3,56.028 71.8,49.428 65.3,45.828zM43.4,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2c-0.3,-0.7 -0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C45.3,56.528 44.5,57.328 43.4,57.328L43.4,57.328zM64.6,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2s-0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C66.5,56.528 65.6,57.328 64.6,57.328L64.6,57.328z"
+        android:strokeWidth="1"
+        android:strokeColor="#00000000" />
+</vector>
--- a/android/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml
+++ b/android/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml
@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@drawable/ic_launcher_background" />
+    <foreground android:drawable="@drawable/ic_launcher_foreground" />
+    <monochrome android:drawable="@drawable/ic_launcher_foreground" />
+</adaptive-icon>
--- a/android/app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml
+++ b/android/app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml
@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@drawable/ic_launcher_background" />
+    <foreground android:drawable="@drawable/ic_launcher_foreground" />
+    <monochrome android:drawable="@drawable/ic_launcher_foreground" />
+</adaptive-icon>
--- a/android/app/src/main/res/mipmap-hdpi/ic_launcher.webp
+++ b/android/app/src/main/res/mipmap-hdpi/ic_launcher.webp
--- a/android/app/src/main/res/mipmap-hdpi/ic_launcher_round.webp
+++ b/android/app/src/main/res/mipmap-hdpi/ic_launcher_round.webp
--- a/android/app/src/main/res/mipmap-mdpi/ic_launcher.webp
+++ b/android/app/src/main/res/mipmap-mdpi/ic_launcher.webp
--- a/android/app/src/main/res/mipmap-mdpi/ic_launcher_round.webp
+++ b/android/app/src/main/res/mipmap-mdpi/ic_launcher_round.webp
--- a/android/app/src/main/res/mipmap-xhdpi/ic_launcher.webp
+++ b/android/app/src/main/res/mipmap-xhdpi/ic_launcher.webp
--- a/android/app/src/main/res/mipmap-xhdpi/ic_launcher_round.webp
+++ b/android/app/src/main/res/mipmap-xhdpi/ic_launcher_round.webp
--- a/android/app/src/main/res/mipmap-xxhdpi/ic_launcher.webp
+++ b/android/app/src/main/res/mipmap-xxhdpi/ic_launcher.webp
--- a/android/app/src/main/res/mipmap-xxhdpi/ic_launcher_round.webp
+++ b/android/app/src/main/res/mipmap-xxhdpi/ic_launcher_round.webp
--- a/android/app/src/main/res/mipmap-xxxhdpi/ic_launcher.webp
+++ b/android/app/src/main/res/mipmap-xxxhdpi/ic_launcher.webp
--- a/android/app/src/main/res/mipmap-xxxhdpi/ic_launcher_round.webp
+++ b/android/app/src/main/res/mipmap-xxxhdpi/ic_launcher_round.webp
--- a/android/app/src/main/res/values/strings.xml
+++ b/android/app/src/main/res/values/strings.xml
@ -0,0 +1,3 @@
+<resources>
+    <string name="app_name">Mitbringsl</string>
+</resources>
--- a/android/app/src/main/res/values/themes.xml
+++ b/android/app/src/main/res/values/themes.xml
@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+
+    <style name="Theme.Mitbringsl" parent="android:Theme.Material.Light.NoActionBar" />
+</resources>
--- a/android/app/src/main/res/xml/backup_rules.xml
+++ b/android/app/src/main/res/xml/backup_rules.xml
@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+   Sample backup rules file; uncomment and customize as necessary.
+   See https://developer.android.com/guide/topics/data/autobackup
+   for details.
+   Note: This file is ignored for devices older than API 31
+   See https://developer.android.com/about/versions/12/backup-restore
+-->
+<full-backup-content>
+    <!--
+   <include domain="sharedpref" path="."/>
+   <exclude domain="sharedpref" path="device.xml"/>
+-->
+</full-backup-content>
--- a/android/app/src/main/res/xml/data_extraction_rules.xml
+++ b/android/app/src/main/res/xml/data_extraction_rules.xml
@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+   Sample data extraction rules file; uncomment and customize as necessary.
+   See https://developer.android.com/about/versions/12/backup-restore#xml-changes
+   for details.
+-->
+<data-extraction-rules>
+    <cloud-backup>
+        <!-- TODO: Use <include> and <exclude> to control what is backed up.
+        <include .../>
+        <exclude .../>
+        -->
+    </cloud-backup>
+    <!--
+    <device-transfer>
+        <include .../>
+        <exclude .../>
+    </device-transfer>
+    -->
+</data-extraction-rules>
--- a/android/app/src/test/java/com/example/mitbringsl/ui/main/MainScreenViewModelTest.kt
+++ b/android/app/src/test/java/com/example/mitbringsl/ui/main/MainScreenViewModelTest.kt
@ -0,0 +1,12 @@
+package com.example.mitbringsl.ui.main
+
+import junit.framework.TestCase.assertNotNull
+import org.junit.Test
+
+class MainScreenViewModelTest {
+  @Test
+  fun viewModel_canBeConstructed() {
+    val viewModel = MainScreenViewModel()
+    assertNotNull(viewModel)
+  }
+}
--- a/android/build.gradle.kts
+++ b/android/build.gradle.kts
@ -0,0 +1,9 @@
+// Top-level build file where you can add configuration options common to all sub-projects/modules.
+plugins {
+  alias(libs.plugins.android.application) apply false
+  alias(libs.plugins.compose.compiler) apply false
+  alias(libs.plugins.hilt) apply false
+  alias(libs.plugins.kotlin.serialization) apply false
+  alias(libs.plugins.ksp) apply false
+  alias(libs.plugins.room) apply false
+}
--- a/android/gradle.properties
+++ b/android/gradle.properties
@ -0,0 +1,29 @@
+# Project-wide Gradle settings.
+# IDE (e.g. Android Studio) users:
+# Gradle settings configured through the IDE *will override*
+# any settings specified in this file.
+# For more details on how to configure your build environment visit
+# http://www.gradle.org/docs/current/userguide/build_environment.html
+# Specifies the JVM arguments used for the daemon process.
+# The setting is particularly useful for tweaking memory settings.
+org.gradle.jvmargs=-Xmx2048m -Dfile.encoding=UTF-8
+# Enables Gradle Build Cache.
+# See https://docs.gradle.org/current/userguide/build_cache.html
+org.gradle.caching=true
+# Enables Gradle Configuration Cache, the preferred Gradle execution mode.
+# See https://docs.gradle.org/current/userguide/configuration_cache.html
+org.gradle.configuration-cache=true
+# When configured, Gradle will run in incubating parallel mode.
+# This option should only be used with decoupled projects. More details, visit
+# http://www.gradle.org/docs/current/userguide/multi_project_builds.html#sec:decoupled_projects
+# org.gradle.parallel=true
+# AndroidX package structure to make it clearer which packages are bundled with the
+# Android operating system, and which are packaged with your app"s APK
+# https://developer.android.com/topic/libraries/support-library/androidx-rn
+android.useAndroidX=true
+# Kotlin code style for this project: "official" or "obsolete":
+kotlin.code.style=official
+# Enables namespacing of each library's R class so that its R class includes only the
+# resources declared in the library itself and none from the library's dependencies,
+# thereby reducing the size of the R class for that library
+android.nonTransitiveRClass=true
--- a/android/gradle/libs.versions.toml
+++ b/android/gradle/libs.versions.toml
@ -0,0 +1,90 @@
+[versions]
+androidGradlePlugin = "9.0.1"
+androidxCore = "1.18.0"
+androidxLifecycle = "2.10.0"
+androidxActivity = "1.13.0"
+androidxComposeBom = "2026.03.01"
+androidxTest = "1.7.0"
+androidxTestExt = "1.3.0"
+androidxTestRunner = "1.7.0"
+androidxTestEspresso = "3.7.0"
+coroutines = "1.10.2"
+hilt = "2.60.1"
+junit = "4.13.2"
+kotlin = "2.3.20"
+ksp = "2.3.11"
+nav3Core = "1.0.1"
+lifecycleViewmodelNav3 = "2.10.0"
+okhttp = "4.12.0"
+retrofit = "2.11.0"
+room = "2.7.2"
+serialization = "1.8.1"
+workmanager = "2.10.2"
+
+[libraries]
+# Core
+androidx-core-ktx = { module = "androidx.core:core-ktx", version.ref = "androidxCore" }
+androidx-activity-compose = { module = "androidx.activity:activity-compose", version.ref = "androidxActivity" }
+
+# Compose BOM
+androidx-compose-bom = { group = "androidx.compose", name = "compose-bom", version.ref = "androidxComposeBom" }
+androidx-compose-material3 = { group = "androidx.compose.material3", name = "material3" }
+androidx-compose-ui = { group = "androidx.compose.ui", name = "ui" }
+androidx-compose-ui-tooling-preview = { group = "androidx.compose.ui", name = "ui-tooling-preview" }
+androidx-compose-ui-test-junit4 = { group = "androidx.compose.ui", name = "ui-test-junit4" }
+androidx-compose-ui-tooling = { group = "androidx.compose.ui", name = "ui-tooling" }
+androidx-compose-ui-test-manifest = { group = "androidx.compose.ui", name = "ui-test-manifest" }
+
+# Lifecycle & ViewModel
+androidx-lifecycle-viewmodel-compose = { module = "androidx.lifecycle:lifecycle-viewmodel-compose", version.ref = "androidxLifecycle" }
+androidx-lifecycle-runtime-compose = { module = "androidx.lifecycle:lifecycle-runtime-compose", version.ref = "androidxLifecycle" }
+androidx-lifecycle-runtime-ktx = { module = "androidx.lifecycle:lifecycle-runtime-ktx", version.ref = "androidxLifecycle" }
+
+# Navigation 3
+androidx-navigation3-runtime = { module = "androidx.navigation3:navigation3-runtime", version.ref = "nav3Core" }
+androidx-navigation3-ui = { module = "androidx.navigation3:navigation3-ui", version.ref = "nav3Core" }
+androidx-lifecycle-viewmodel-navigation3 = { module = "androidx.lifecycle:lifecycle-viewmodel-navigation3", version.ref = "lifecycleViewmodelNav3" }
+
+# Hilt (DI)
+hilt-android = { module = "com.google.dagger:hilt-android", version.ref = "hilt" }
+hilt-android-compiler = { module = "com.google.dagger:hilt-android-compiler", version.ref = "hilt" }
+hilt-navigation-compose = { module = "androidx.hilt:hilt-navigation-compose", version = "1.2.0" }
+
+# Room (local DB)
+room-runtime = { module = "androidx.room:room-runtime", version.ref = "room" }
+room-ktx = { module = "androidx.room:room-ktx", version.ref = "room" }
+room-compiler = { module = "androidx.room:room-compiler", version.ref = "room" }
+
+# Retrofit + OkHttp (network)
+retrofit = { module = "com.squareup.retrofit2:retrofit", version.ref = "retrofit" }
+retrofit-serialization = { module = "com.squareup.retrofit2:converter-kotlinx-serialization", version.ref = "retrofit" }
+okhttp = { module = "com.squareup.okhttp3:okhttp", version.ref = "okhttp" }
+okhttp-logging = { module = "com.squareup.okhttp3:logging-interceptor", version.ref = "okhttp" }
+
+# Kotlinx Serialization
+kotlinx-serialization-json = { module = "org.jetbrains.kotlinx:kotlinx-serialization-json", version.ref = "serialization" }
+
+# Coroutines
+kotlinx-coroutines-android = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-android", version.ref = "coroutines" }
+
+# WorkManager
+workmanager-ktx = { module = "androidx.work:work-runtime-ktx", version.ref = "workmanager" }
+hilt-work = { module = "androidx.hilt:hilt-work", version = "1.2.0" }
+hilt-work-compiler = { module = "androidx.hilt:hilt-compiler", version = "1.2.0" }
+
+# Tests
+androidx-test-core = { module = "androidx.test:core", version.ref = "androidxTest" }
+androidx-test-ext-junit = { module = "androidx.test.ext:junit", version.ref = "androidxTestExt" }
+androidx-test-espresso-core = { module = "androidx.test.espresso:espresso-core", version.ref = "androidxTestEspresso" }
+androidx-test-runner = { module = "androidx.test:runner", version.ref = "androidxTestRunner" }
+junit = { module = "junit:junit", version.ref = "junit" }
+kotlinx-coroutines-test = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-test", version.ref = "coroutines" }
+
+[plugins]
+android-application = { id = "com.android.application", version.ref = "androidGradlePlugin" }
+compose-compiler = { id = "org.jetbrains.kotlin.plugin.compose", version.ref = "kotlin" }
+hilt = { id = "com.google.dagger.hilt.android", version.ref = "hilt" }
+kotlin-android = { id = "org.jetbrains.kotlin.android", version.ref = "kotlin" }
+kotlin-serialization = { id = "org.jetbrains.kotlin.plugin.serialization", version.ref = "kotlin" }
+ksp = { id = "com.google.devtools.ksp", version.ref = "ksp" }
+room = { id = "androidx.room", version.ref = "room" }
--- a/android/gradle/wrapper/gradle-wrapper.jar
+++ b/android/gradle/wrapper/gradle-wrapper.jar
--- a/android/gradle/wrapper/gradle-wrapper.properties
+++ b/android/gradle/wrapper/gradle-wrapper.properties
@ -0,0 +1,8 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.1.0-bin.zip
+distributionSha256Sum=a17ddd85a26b6a7f5ddb71ff8b05fc5104c0202c6e64782429790c933686c806
+networkTimeout=10000
+validateDistributionUrl=true
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
--- a/android/gradlew
+++ b/android/gradlew
@ -0,0 +1,172 @@
+#!/usr/bin/env sh
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS=""
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=$((i+1))
+    done
+    case $i in
+        (0) set -- ;;
+        (1) set -- "$args0" ;;
+        (2) set -- "$args0" "$args1" ;;
+        (3) set -- "$args0" "$args1" "$args2" ;;
+        (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=$(save "$@")
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
+if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
+  cd "$(dirname "$0")"
+fi
+
+exec "$JAVACMD" "$@"
--- a/android/gradlew.bat
+++ b/android/gradlew.bat
@ -0,0 +1,84 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
--- a/android/settings.gradle.kts
+++ b/android/settings.gradle.kts
@ -0,0 +1,33 @@
+pluginManagement {
+    repositories {
+        google {
+            content {
+                includeGroupByRegex("androidx.*")
+                includeGroupByRegex("com\\.android.*")
+                includeGroupByRegex("com\\.google.*")
+            }
+        }
+        mavenCentral()
+        gradlePluginPortal()
+    }
+}
+dependencyResolutionManagement {
+    repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
+    repositories {
+        google {
+            content {
+                includeGroupByRegex("androidx.*")
+                includeGroupByRegex("com\\.android.*")
+                includeGroupByRegex("com\\.google.*")
+            }
+        }
+        mavenCentral()
+    }
+}
+
+plugins {
+    id("org.gradle.toolchains.foojay-resolver-convention") version "1.0.0"
+}
+
+rootProject.name = "Mitbringsl"
+include(":app")