Track is the app's normalized song model and QueueItemRef its thin queue
identity -- consumed app-wide (queue, cover, context menus, sharing, lucky-mix,
library browse), not a playback-internal detail. They lived in
features/playback/store/playerStoreTypes, forcing ~115 core/feature files to
reach into the playback feature for the central media type.
Move the two interfaces to lib/media/trackTypes; playerStoreTypes keeps
PlayerState and now imports them from lib. 115 importers repointed (mixed
'PlayerState, Track' lines split so PlayerState stays). Pure type move (erased at
runtime). tsc 0, lint 0.
The queue-resolver family (queueTrackResolver, queueRestore, queueItemRef,
queueTrackView) runtime-imports usePlayerStore / playerStoreTypes — it is the
playback engine's thin-state queue subsystem, not shared library infra. It sat
in utils/library only because it queries the local index. Co-locate into
features/playback/store so those edges become intra-feature; its remaining deps
(advancedSearchLocal, libraryReady, serverLookup, serverIndexKey, authStore) are
plain core/infra (feature -> infra, no inversion).
Removes 4 of the 6 store/utils -> feature runtime inversions that blocked the
utils/library -> lib move. 8 files moved, 46 consumers rewritten. tsc 0, lint 0,
targeted suites green.
Relocate the playback/queue/transport/audio-output engine out of the type-first
store/ + utils/playback/ + utils/audio/ dirs into a cohesive src/features/playback/,
structure-preserving:
store/<x> -> features/playback/store/<x>
store/audioListenerSetup/<x> -> features/playback/store/audioListenerSetup/<x>
utils/playback/<x> -> features/playback/utils/playback/<x>
utils/audio/<x> -> features/playback/utils/audio/<x>
184 files moved (107 source + 77 tests), 365 consumers rewritten. Pure move — no
behavior change, no state-split (the playerStore state-split stays a separate M5
question). Enabled by this session's decouple seams (artist/offline/orbit/auth →
core registries), so the engine carries no inbound core->feature inversion: store/
now holds only the 50 cross-cutting global stores (auth family, the seams, library
index, UI/settings stores).
KEPT OUT of the move (would re-create global->engine edges): the 3 pure config
helpers utils/audio/{loudnessPreAnalysisSlider,hiResCrossfadeResample} +
utils/playback/autodjOverlapCap (authStore + settings UI read them — they stay in
utils/). Ambiguous view-state stores (eqStore, queueToolbarStore,
playerBarLayoutStore) stay global (no engine imports).
Consumers use DEEP paths (@/features/playback/...), no barrel — matches the lib/
approach and avoids barrel-mock-collapse across the 140 usePlayerStore consumers.
Two tolerated type-only core->feature edges remain (localPlaybackStore->QueueItemRef,
localPlaybackMigration->HotCacheEntry, both erased).
tsc 0, lint 0, full suite 319/2353 green, iron-rule clean (no runtime store->feature
import). Behavior-touching only via the prerequisite bridge seam (already QA-flagged);
the move itself is pure.
Psychotoxical