Audit v2 priority #9. Track rows on AlbumDetail, PlaylistDetail,
LikedTab, HistoryTab, and SearchScreen now render the currently-
playing track's title in accent (primary) color so the user can
spot "this is what's playing" while scrolling a list.
Pattern: each screen pulls a PlayerViewModel via hiltViewModel(),
reads state.currentTrack?.id, threads it through to its track row
composable as nowPlaying: Boolean. Row picks titleColor based on
the flag. No new infrastructure — just a thread-through.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>