Absorb v1.2.1 - Sync & Progress Fixes

Multi-Device Sync

• Resume position now uses last-write-wins timestamp comparison between local and server
• Playing a book on device A, pausing, then pressing play on device B correctly picks up the newer position
• Server session created for downloaded books when online, enabling full sync during local playback

Absorbing Screen

• Unified Sync/Stop & Sync button replaces the two separate buttons
  • No playback: Shows "Sync", pulls fresh progress from server
  • During playback: Shows "Stop & Sync", stops playback, syncs, refreshes
  • Offline: Shows "Stop", stops playback only

Progress Refresh

• Sync and refresh now updates progress bars, chapter indicators, and percentages across all screens immediately
• Home screen continue listening cards now reactively rebuild on progress changes
• Refreshing on any tab updates the absorbing cards too since IndexedStack keeps all tabs live
• Refresh flow: flush pending local, pull fresh server data, clear stale overrides, write server data to local, notify all listeners

Files Changed

• lib/services/audio_player_service.dart - timestamp comparison in _playFromLocal and _playFromServer
• lib/providers/library_provider.dart - refresh() override clearing, SharedPreferences writeback
• lib/screens/absorbing_screen.dart - unified sync button, _pullRefresh
• lib/widgets/book_card.dart - context.read changed to context.watch