fix(plex): the player's settings panel is a tab list with named, touch-sized rows

- Its section switch is `ui/Tabs` (new `tone="media"` paint for the dark chrome) with a wired
  tabpanel; the panel opens with the focus on the selected tab.
- On/off rows are `CheckRow` (the whole row, 44 on touch), the "no background" checkbox too.
- Every slider and the four colour wells carry the name their row shows.
- The clock's date-style buttons reach the touch target.

frontend/src/components/ui/pressableSelectable.contract.test.ts

@@ -27,7 +27,7 @@ const PLAIN: Record<string, [number, string]> = {
   "PlaylistsRail.tsx": [1, "the load-error retry"],
   "PlexCollectionEditor.tsx": [1, "a checkbox row in a picker"],
   "PlexInfo.tsx": [1, "the rating filter (a number)"],
-  "PlexPlayerSettings.tsx": [2, "setting options"],
+  "PlexPlayerSettings.tsx": [1, "the clock's date-style options"],
   "PlexPlaylistAdd.tsx": [1, "a checkbox row in a picker"],
   "PlexPlaylistView.tsx": [1, "a show's poster stack (aria-hidden)"],
   "PlexSearchBox.tsx": [1, "a listbox option"],