Album/artist downloads expand to tracks with pinned parent metadata,
aggregate progress, container deletes with reference-counted album
covers, and a Music tab on the downloads screen with fully offline
album playback. Home rows include music libraries (fixes plex hub
items being filtered to video types) and audio playlists join
download/sync rules.
The aired-order rework can sweep correctly-placed Specials into "download
next N"; this toggle lets users opt out. Shown only for whole shows
(reusing FocusableSwitchListTile via an optional toggle on the shared
option-picker dialog), remembered across opens via a BoolPref
(default on = unchanged behavior). Filters Specials at the single
collect choke point (_collectPlayable), with a guard so explicitly
downloading the Specials season still queues its episodes.
Progress ring now measures completion against the episodes actually queued (episodes.length) instead of the show's full leafCount, and advances smoothly using per-episode progress. The completed show/season download button reopens the download-options dialog (with a Delete row) so users can fetch more episodes or switch to sync instead of only deleting.
edde746