Delete the entire Qobuz downloader implementation (qobuz.go, qobuz_test.go)
including all API clients, search, metadata, download, and track matching
code. Empty the builtInProviderRegistry now that all built-in providers are
retired. Remove Qobuz-specific exports (SearchQobuzAll, GetQobuzMetadata,
ParseQobuzURLExport) and the downloadWithBuiltInQobuz adapter. Stub out
PreWarmTrackCache and cache management since no built-in providers remain.
Move qobuz cover upgrade regex to cover.go. Update Dart screens, providers,
and localization strings for the provider-agnostic UI.
- Add configurable YouTube Opus (96-256kbps) and MP3 (96-320kbps) bitrates
- Improve title matching with loose normalization for symbol-heavy tracks
- Add SpotubeDL engine v2 fallback for MP3 requests
- Improve filename sanitization in track metadata screen
- Bump version to 3.6.9+82