- Add all_artists field to LocalAlbum for accurate artist matching
- Consolidate duplicate artists with case differences (e.g., "Alice in Chains" / "Alice In Chains")
- Fix album count calculation to avoid double-counting
- Show Various Artists albums under contributing artists
- Handle multi-artist names (e.g., "A, B, C") with union matching
- Add cleanup missing files feature in settings maintenance section
- Improve settings UI with side-by-side Maintenance/Danger Zone layout
- Add status indicator during cleanup operations