#392 shipped track.liked / track.unliked but skipped the album +
artist symmetric pairs. Closes that gap so the Flutter Liked tab's
albums and artists sub-lists can listen for changes the same way
the tracks sub-list will (#402 wire-up lands next commit).
publishLikeEvent already handles the entity_type dispatch; the four
handler call sites just need the new lines.
For #402 follow-up to #392.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>