This commit introduces several new features and improvements to Spotube:
- **DAB Music Integration:** Adds DAB Music as a new high-quality audio source, with support for searching, streaming, and downloading tracks.
- **Playback Quality Display:** Adds a UI element to the player to display the actual audio quality of the currently playing stream.
- **Performance Optimization:** Improves the startup and shutdown performance of the desktop application.
- **Dependency Fix:** Resolves a dependency conflict with `dio_retry` by implementing a custom retry interceptor.
* feat: add youtube engine abstraction and yt-dlp integration
* chore: add yt-dlp as optional dependency
* feat: implement custom path support for youtube engines
* chore: check for custom path in setting engine select dropdown
* chore: update yt_dlp_dart
* chore: setting video url instead of video id in fetchSiblings
* feat: implement NewPipe engine
* chore: update local path to git url for flutter_new_pipe_extractor package
* chore: fix android build isn't working
* chore: fix routes not working when initially signing in
* refactor: drop fallback support to different sources
* feat: add caching support with track metadata
* feat(settings): add cache music toggle
* fix(mobile): cache dir not open-able
* feat(local folder): add cache export/clear actions and size of the folder
* chore: ios deps upgrades
* chore: upgrade lint flutter version
* chore: lint secrets causing error
* cd: invalid value for env var
* feat: add invidious audio source with automatic track switch even on server playback endpoint
* fix: switching to different source on playback endpoint error not working
* chore: update invidious version
* feat: invidious instances customizability
