Fix YouTube Sonos metadata fallback and queue display

[Darkatek7]

Validation summary

• Changed file scope: Sonos YouTube playback metadata, queue fallback, and queue display formatting
• Required checks run:
  • dotnet test SonosControl.sln --verbosity minimal: PASS
• Optional checks run:
  • python3 verify_mobile_smoke.py: N/A
• Notes: nightly includes the verified Sonos YouTube metadata/session fallback, queue parser fix, and duplicate artist-title cleanup. Manual QA on speaker küch showed real Madison Beer queue metadata in the app queue and now-playing path.