Fix: Resolve list selection crash & update to minimal flat app icon

- ListDetailViewModel & Screen: set listId safely via setListId() avoiding SavedStateHandle null crashes
- Navigation: pass listId = key.listId explicitly into ListDetailScreen
- App Icon: replace 3D icon with a clean, minimal flat line-art shopping bag & checkmark icon suited for Samsung One UI & stock Android adaptive icon masks
- ADB reinstall & launch verified ✅

android/app/src/main/java/com/example/mitbringsl/Navigation.kt

@@ -37,6 +37,7 @@ fun MainNavigation(sessionManager: SessionManager) {
             }
             entry<ListDetailNavKey> { key ->
                 ListDetailScreen(
+                    listId = key.listId,
                     onBack = { backStack.removeLastOrNull() }
                 )
             }

android/app/src/main/java/com/example/mitbringsl/ui/detail/ListDetailScreen.kt

@@ -29,10 +29,15 @@ import com.example.mitbringsl.data.local.entity.ItemEntity
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun ListDetailScreen(
+    listId: String,
     onBack: () -> Unit,
     modifier: Modifier = Modifier,
     viewModel: ListDetailViewModel = hiltViewModel(),
 ) {
+    LaunchedEffect(listId) {
+        viewModel.setListId(listId)
+    }
+
     val items by viewModel.items.collectAsStateWithLifecycle()
     val query by viewModel.query.collectAsStateWithLifecycle()
     val suggestions by viewModel.suggestions.collectAsStateWithLifecycle()

android/app/src/main/java/com/example/mitbringsl/ui/detail/ListDetailViewModel.kt

@@ -1,34 +1,43 @@
 package com.example.mitbringsl.ui.detail
 
-import androidx.lifecycle.SavedStateHandle
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import com.example.mitbringsl.data.local.entity.ItemEntity
 import com.example.mitbringsl.data.remote.api.MitbringslApi
 import com.example.mitbringsl.data.repository.ShoppingRepository
 import dagger.hilt.android.lifecycle.HiltViewModel
+import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.FlowPreview
 import kotlinx.coroutines.flow.*
 import kotlinx.coroutines.launch
 import javax.inject.Inject
 
-@OptIn(FlowPreview::class)
+@OptIn(FlowPreview::class, ExperimentalCoroutinesApi::class)
 @HiltViewModel
 class ListDetailViewModel @Inject constructor(
     private val repository: ShoppingRepository,
     private val api: MitbringslApi,
-    savedStateHandle: SavedStateHandle,
 ) : ViewModel() {
 
-    val listId: String = checkNotNull(savedStateHandle["listId"])
+    private val _listId = MutableStateFlow<String?>(null)
 
-    val items: StateFlow<List<ItemEntity>> = repository.observeItems(listId)
+    val items: StateFlow<List<ItemEntity>> = _listId
+        .filterNotNull()
+        .flatMapLatest { id -> repository.observeItems(id) }
         .stateIn(
             scope = viewModelScope,
             started = SharingStarted.WhileSubscribed(5000),
             initialValue = emptyList()
         )
 
+    fun setListId(id: String) {
+        if (_listId.value != id) {
+            _listId.value = id
+        }
+    }
+
+    val currentListId: String get() = _listId.value ?: ""
+
     private val _query = MutableStateFlow("")
     val query: StateFlow<String> = _query.asStateFlow()
 
@@ -61,10 +70,11 @@ class ListDetailViewModel @Inject constructor(
     }
 
     fun addItem(name: String, quantity: String? = null) {
+        val targetListId = _listId.value ?: return
         if (name.isBlank()) return
         val qty = quantity?.trim()?.takeIf { it.isNotEmpty() }
         viewModelScope.launch {
-            repository.addItem(listId, name.trim(), qty)
+            repository.addItem(targetListId, name.trim(), qty)
             _query.value = ""
             _suggestions.value = emptyList()
         }

android/app/src/main/res/values/colors.xml

@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
-    <color name="ic_launcher_background_color">#1B1B2F</color>
+    <color name="ic_launcher_background_color">#151829</color>
 </resources>