Add per-page element customization and panel settings polish

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.

Yattee/Views/Components/VideoRowView.swift

@@ -26,6 +26,8 @@ struct VideoRowView: View {
     var index: Int? = nil
     /// When true, disables internal tap handling so parent view can handle all taps.
     var disableInternalTapHandling: Bool = false
+    /// When false, hides the thumbnail (e.g. details panel related page setting).
+    var showThumbnail: Bool = true
 
     // Platform-specific fonts
     #if os(tvOS)
@@ -95,8 +97,10 @@ struct VideoRowView: View {
             }
             
             // Thumbnail
-            thumbnailView
-                .zoomTransitionSource(id: video.id)
+            if showThumbnail {
+                thumbnailView
+                    .zoomTransitionSource(id: video.id)
+            }
 
             // Info
             infoView