- Add AppViewModel to manage app-level state and handle 401 responses
- Implement automatic logout when API returns 401 Unauthorized
- Add persistent logout state using existing hasFinishedSetup flag
- Move NavigationStack outside TabView to enable automatic TabBar hiding
- Update API classes to send UnauthorizedAPIResponse notifications
- TabBar now hides automatically when navigating to detail views
- Replace multiple boolean properties with single OfflineBookmarkSyncState enum
- Add Use Case pattern for OfflineSyncManager with dependency injection
- Simplify LocalBookmarksSyncView using state-driven UI with external bindings
- Convert OfflineBookmarksViewModel to use @Observable instead of ObservableObject
- Move credentials from Core Data to Keychain for better persistence
- Implement comprehensive database migration for App Group containers
- Add structured logging throughout sync operations and API calls
Architecture improvements follow MVVM principles with clean separation of concerns.