- Refactor EmbedM4AMetadata to use streaming instead of loading entire file
- Use os.Open + ReadAt instead of os.ReadFile for memory efficiency
- Atomic file replacement via temp file + rename for safer writes
- New helper functions: findAtomInRange, readAtomHeaderAt, copyRange, buildUdtaAtom
- Refactor GetM4AQuality to use streaming with findAudioSampleEntry
- Use NewHTTPClientWithTimeout helper in lyrics.go, qobuz.go, tidal.go
- Update CHANGELOG with performance improvements and MP3 metadata support
- Add lyrics mode setting (embed/external/both) for saving lyrics
- Implement SaveLRCFile() in Go backend for all providers (Tidal, Qobuz, Amazon)
- Fix locale parsing in app.dart to handle country codes (e.g., pt_PT -> Locale('pt', 'PT'))
- Change Portuguese label from Portugal to Brasil in language settings
- Add extension manager, manifest, runtime, providers, settings
- Add extension provider and UI pages (extensions, detail, priority)
- Add download service picker widget
- Add metadata provider priority page
- Add source field to Track model for extension tracking
- Add skipBuiltInFallback manifest option to skip built-in providers
- Update download queue to use source extension first
- Add extension upgrade support without data loss
zarzet