fix(flutter): analyze errors after Plan C provider migrations

- cache_first.dart: backtick-fence List<T> doc comment to dodge
  unintended_html_in_doc_comment.
- library_providers.dart:163: switch single-row insert to
  insertAllOnConflictUpdate; Batch only exposes the *AllOnConflict*
  variant.
- 5 test files: StreamProvider.overrideWith takes Create<Stream<T>>,
  not Create<Future<T>>. Wrap data emissions in Stream.value(...).
- artist_detail_screen_test: add models/album.dart import for AlbumRef
  type annotation.
- track_actions_sheet_test: drop _StubLiked extends LikedIdsController
  (notifier no longer exists post-migration); override with
  Stream.value(LikedIds(...)) instead.
- like_button_test: rollback assertion now requires drift writes via
  LikesController. Skip under _skipDrift until libsqlite3-dev lands on
  the runner image (Fable #399). Replace stale .notifier reference
  with likesControllerProvider for completeness.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

flutter_client/lib/cache/cache_first.dart

@@ -13,7 +13,7 @@ import 'dart:async';
 
 /// Wraps the watch + cold-cache fallback pattern. Generic over:
 ///   D — the drift row type (or TypedResult for joins)
-///   T — the result type the caller wants (e.g. List<ArtistRef>)
+///   T — the result type the caller wants (e.g. `List<ArtistRef>`)
 ///
 /// `fetchAndPopulate` is invoked when drift is empty AND `isOnline()`
 /// returns true. It must populate drift via its own side-effect; the