Merge origin/develop into refactor-chromecast

Bring 323 commits of develop (incl. the Expo SDK 56 / TV-branch work) into
the chromecast refactor. Conflict resolutions:

- chapters: take develop's reviewed version (ChapterList/ChapterTicks/
  chapters.ts/test) — adds chapterNameAt, markers API, themed Colors.
- auto-skip: keep chromecast's unified useSegmentSkipper for the phone
  player; restore develop's useCreditSkipper/useIntroSkipper (deleted on
  chromecast) so develop's Controls.tv.tsx compiles. TV->useSegmentSkipper
  migration left as follow-up.
- en.json: union the two player blocks (kept chromecast casting keys +
  develop's subtitle/playback keys).
- TechnicalInfoOverlay/PlatformDropdown: take develop's TV-safe versions
  (kept chromecast's disabled-prop branch, aliased to avoid shadowing the
  @expo/ui disabled modifier).
- SDK 56 fixes: expo-router Router -> ImperativeRouter in cast components;
  ChapterTicks markers API in CastPlayerProgressBar.
- restore utils/profiles/chromecast* (deleted on chromecast, still used by
  PlayButton).

Typecheck passes; bun.lock regenerated against merged package.json.

components/PlayButton.tsx

@@ -327,7 +327,7 @@ export const PlayButton: React.FC<Props> = ({
   ]);
 
   const derivedTargetWidth = useDerivedValue(() => {
-    if (!item || !item.RunTimeTicks) return 0;
+    if (!item?.RunTimeTicks) return 0;
     const userData = item.UserData;
     if (userData?.PlaybackPositionTicks) {
       return userData.PlaybackPositionTicks > 0