Replace the per-tracker json_serializable session classes and account stores with a shared TrackerSession (service-aware persisted validation), a single TrackerAccountStore, a shared TrackerHttpClient, and an AnimeListTrackerBase mixin for MAL/AniList. Scope the per-service rebind guard so a disconnect can't abort a racing profile load. Add migration-safety, MAL refresh, episode-count cache, and content-type tests.
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.
Discover and libraries now fetch only the servers that came online since
the last pass and merge the results; already-loaded servers are not
refetched. Both providers also own their online-servers listener
(registered in the constructor, removed in dispose), so profile switches
no longer leak listeners that kept disposed providers refetching.
Resolution now considers parentChain ancestors (newest event wins) and
watched patches set container leaf counts, so container marks reach
descendant cards and vice versa.
edde746