- Add per-item notes editable in the detail and edit screens, synced
between desktop and Android
- Guard against duplicates by external ID and by type/year/title,
mirroring the desktop findDuplicate logic in MediaDao
- Wrap multi-step database operations in Room transactions
- Disable Android auto backup and remove the destructive Room
migration fallback so schema bumps fail loudly instead of wiping data
- Bound crypto envelope KDF parameters when reading untrusted headers
- Handle malformed server responses in SyncClient instead of crashing
- Extend settings, database, and image cache on the desktop side
