Phase 5 of the player panels redesign:
- Per-page element toggles now rendered and editable for every page:
comments (author avatars), related (thumbnails), chapters (thumbnails),
queue (previously played section), tracks (video/audio/subtitles/speed
sections)
- Page bar labels toggle (icons-only bar shows the selected page's name)
- Layout mode schematic diagram in the details panel settings
- NEW badge machinery for future page types (versionAdded on PanelPageType)
- Typed per-page settings accessors on PanelPageConfiguration and VM update
helpers for each page kind
- Unit tests for per-page settings round-trip and accessor fallbacks
The standalone quality selector sheet is unaffected: section gating defaults
to everything visible and only the embedded tracks page passes preset
settings through.
The row's accessibilityLabel was the debug string video.row.<id>, so
VoiceOver read a raw YouTube ID for every row. Build the label from the
DeArrow-aware display title, author name, and duration instead; the
accessibilityIdentifier stays unchanged for UI tests.
