- Move explore JSON decode/encode to compute() isolate to avoid blocking main thread
- Memoize search sort results (artists/albums/playlists/tracks) in HomeTab; invalidate on new query
- Extract _DownloadedOrRemoteCover StatefulWidget with proper embedded-cover lifecycle management
- Replace O(playlists x tracks) in-memory playlist picker check with SQL loadPlaylistPickerSummaries query
- Add FutureProvider.family (libraryPlaylistPickerSummariesProvider) invalidated on all playlist mutations
- Memoize _buildQueueHistoryStats, localPathMatchKeys, and localSingleItems in QueueTab
- Add coverCacheWidthForViewport util; apply memCacheWidth/cacheWidth based on real DPR across all album/playlist/track screens
- Convert sync file ops in TrackMetadataScreen to async; use mtime+size as validation token
- Fetch Deezer album nb_tracks in parallel via fetchAlbumTrackCounts