refactor(waveform): move waveform data pipeline back to audio-core

The M0 pilot mis-membered the waveform data pipeline into features/waveform,
creating a core->feature inversion: ~12 audio-core files in store/ imported
refreshWaveformForTrack / fetchWaveformBins / bumpWaveformRefreshGen from the
feature barrel. These are playback coordination (write waveformBins into
playerStore on track change, last-write-wins gen guard), not seekbar rendering.

Move waveformRefresh + waveformRefreshGen (+ tests) to src/store/ and
waveformParse (+ test) to src/utils/waveform/ (beside waveformSilence). The
feature now holds only the seekbar UI (WaveformSeek/SeekbarPreview + their
hooks/render utils); its barrel exports UI only. Core consumers import the
pipeline directly from @/store/*. Restores the no-core->feature-inversion rule.

src/features/waveform/index.ts

@@ -1,11 +1,15 @@
 /**
- * Waveform seekbar feature — the canvas seekbar, its waveform-bin loading, and
- * the per-track refresh generation guard. Co-located mirror of `cover/` /
- * `music-network/`. `waveformSilence` stays in `utils/waveform/` (crossfade /
- * auto-dj concern, not seekbar rendering).
+ * Waveform seekbar feature — the canvas seekbar (rendering only). Co-located
+ * mirror of `cover/` / `music-network/`.
+ *
+ * The waveform DATA pipeline is audio-core, NOT this feature: the audio engine
+ * calls it on track change to write `waveformBins` into the player store. It
+ * therefore lives in core, consumed directly (never via this barrel):
+ *   - `@/store/waveformRefresh` — `refreshWaveformForTrack` / `fetchWaveformBins`
+ *   - `@/store/waveformRefreshGen` — `bumpWaveformRefreshGen` / `getWaveformRefreshGen`
+ *   - `@/utils/waveform/waveformParse` — bin coercion (alongside `waveformSilence`,
+ *     the crossfade / auto-dj silence helper)
+ * Keeping these in core preserves the iron rule (no core→feature inversion).
  */
 export { default as WaveformSeek } from './components/WaveformSeek';
 export { SeekbarPreview } from './components/WaveformSeekPreview';
-export { fetchWaveformBins, refreshWaveformForTrack } from './store/waveformRefresh';
-export type { WaveformCachePayload } from './store/waveformRefresh';
-export { bumpWaveformRefreshGen, getWaveformRefreshGen } from './store/waveformRefreshGen';

src/store/applyQueueHistorySnapshot.ts

@@ -20,7 +20,7 @@ import {
   type QueueUndoSnapshot,
 } from './queueUndo';
 import { refreshLoudnessForTrack } from './loudnessRefresh';
-import { refreshWaveformForTrack } from '@/features/waveform';
+import { refreshWaveformForTrack } from '@/store/waveformRefresh';
 import { stopRadio } from './radioPlayer';
 import { clearAllPlaybackScheduleTimers } from './scheduleTimers';
 import { syncUserQueueMutationToServer } from './queueSync';

src/store/applyServerPlayQueue.idle.test.ts

@@ -27,7 +27,7 @@ vi.mock('./pausedRestorePrepare', () => ({
   preparePausedRestoreOnStartup: vi.fn(),
 }));
 
-vi.mock('@/features/waveform', () => ({
+vi.mock('@/store/waveformRefresh', () => ({
   refreshWaveformForTrack: vi.fn(),
 }));
 

src/store/applyServerPlayQueue.ts

@@ -9,7 +9,7 @@ import { useAuthStore } from './authStore';
 import { usePlayerStore } from './playerStore';
 import { preparePausedRestoreOnStartup } from './pausedRestorePrepare';
 import { pushQueueUndoFromGetter } from './queueUndo';
-import { refreshWaveformForTrack } from '@/features/waveform';
+import { refreshWaveformForTrack } from '@/store/waveformRefresh';
 import {
   getIdlePullGeneration,
   isIdleQueuePullSuspended,

src/store/audioEventHandlers.ts

@@ -87,7 +87,7 @@ import {
   getSeekTarget,
   getSeekTargetSetAt,
 } from './seekTargetState';
-import { refreshWaveformForTrack } from '@/features/waveform';
+import { refreshWaveformForTrack } from '@/store/waveformRefresh';
 import { analyzeBoundary, computeWaveformSilence } from '../utils/waveform/waveformSilence';
 import { autodjMaxOverlapCapSec } from '../utils/playback/autodjOverlapCap';
 import {

src/store/audioListenerSetup/audioEngineListeners.ts

@@ -24,8 +24,8 @@ import {
   markNormalizationUiUpdate,
 } from '../playbackThrottles';
 import { usePlayerStore } from '../playerStore';
-import { refreshWaveformForTrack } from '@/features/waveform';
-import { bumpWaveformRefreshGen } from '@/features/waveform';
+import { refreshWaveformForTrack } from '@/store/waveformRefresh';
+import { bumpWaveformRefreshGen } from '@/store/waveformRefreshGen';
 import { setBytePreloadingId } from '../gaplessPreloadState';
 
 type PreloadEventPayload = {

src/store/audioListenerSetup/authSyncListener.ts

@@ -7,8 +7,8 @@ import { invokeAudioSetNormalizationDeduped } from '../normalizationIpcDedupe';
 import { usePlayerStore } from '../playerStore';
 import { clearLoudnessCacheStateForTrackId } from '../loudnessGainCache';
 import { refreshLoudnessForTrack } from '../loudnessRefresh';
-import { refreshWaveformForTrack } from '@/features/waveform';
-import { bumpWaveformRefreshGen } from '@/features/waveform';
+import { refreshWaveformForTrack } from '@/store/waveformRefresh';
+import { bumpWaveformRefreshGen } from '@/store/waveformRefreshGen';
 
 /**
  * Keeps the Rust audio engine in sync whenever the auth store changes

src/store/audioListenerSetup/initialAudioSync.ts

@@ -5,7 +5,7 @@ import { emitNormalizationDebug } from '../normalizationDebug';
 import { invokeAudioSetNormalizationDeduped } from '../normalizationIpcDedupe';
 import { usePlayerStore } from '../playerStore';
 import { refreshLoudnessForTrack } from '../loudnessRefresh';
-import { refreshWaveformForTrack } from '@/features/waveform';
+import { refreshWaveformForTrack } from '@/store/waveformRefresh';
 
 /**
  * One-shot startup sync: pushes the persisted audio settings to the Rust engine

src/store/crossfadePreload.ts

@@ -15,7 +15,7 @@ import {
 import { getBytePreloadingId, setBytePreloadingId } from './gaplessPreloadState';
 import { refreshLoudnessForTrack } from './loudnessRefresh';
 import { usePlayerStore } from './playerStore';
-import { fetchWaveformBins } from '@/features/waveform';
+import { fetchWaveformBins } from '@/store/waveformRefresh';
 
 // Crossfade pre-buffer budget: begin downloading the next track this many
 // seconds before it needs to play (the crossfade start), so a large lossless

src/store/loudnessReseed.test.ts

@@ -39,7 +39,7 @@ vi.mock('./playerStore', () => ({
     setState: hoisted.playerSetStateMock,
   },
 }));
-vi.mock('@/features/waveform', () => ({
+vi.mock('@/store/waveformRefreshGen', () => ({
   bumpWaveformRefreshGen: hoisted.bumpWaveformRefreshGenMock,
 }));
 vi.mock('./loudnessGainCache', () => ({

src/store/loudnessReseed.ts

@@ -3,7 +3,7 @@ import { invoke } from '@tauri-apps/api/core';
 import { getPlaybackIndexKey } from '../utils/playback/playbackServer';
 import { useAuthStore } from './authStore';
 import { usePlayerStore } from './playerStore';
-import { bumpWaveformRefreshGen } from '@/features/waveform';
+import { bumpWaveformRefreshGen } from '@/store/waveformRefreshGen';
 import { clearLoudnessCacheStateForTrackId } from './loudnessGainCache';
 import { resetLoudnessBackfillStateForTrackId } from './loudnessBackfillState';
 

src/store/playTrackAction.ts

@@ -51,7 +51,7 @@ import {
   loudnessGainDbForEngineBind,
 } from './loudnessGainCache';
 import { refreshLoudnessForTrack } from './loudnessRefresh';
-import { fetchWaveformBins, refreshWaveformForTrack } from '@/features/waveform';
+import { fetchWaveformBins, refreshWaveformForTrack } from '@/store/waveformRefresh';
 import { deriveNormalizationSnapshot } from './normalizationSnapshot';
 import { useOrbitStore } from './orbitStore';
 import {

src/store/transportLightActions.ts

@@ -11,7 +11,7 @@ import { clearSeekDebounce } from './seekDebounce';
 import { clearSeekFallbackRetry } from './seekFallbackState';
 import { clearSeekTarget } from './seekTargetState';
 import { tryAcquireTogglePlayLock } from './togglePlayLock';
-import { refreshWaveformForTrack } from '@/features/waveform';
+import { refreshWaveformForTrack } from '@/store/waveformRefresh';
 import { clearAutodjTransitionUi } from './autodjTransitionUi';
 
 type SetState = (

src/store/waveformRefresh.test.ts

@@ -22,18 +22,18 @@ const hoisted = vi.hoisted(() => ({
 }));
 
 vi.mock('@tauri-apps/api/core', () => ({ invoke: hoisted.invokeMock }));
-vi.mock('@/features/waveform/utils/waveformParse', () => ({ coerceWaveformBins: hoisted.coerceWaveformBinsMock }));
+vi.mock('@/utils/waveform/waveformParse', () => ({ coerceWaveformBins: hoisted.coerceWaveformBinsMock }));
 vi.mock('@/store/playerStore', () => ({
   usePlayerStore: {
     getState: () => hoisted.playerSnapshot,
     setState: hoisted.playerSetStateMock,
   },
 }));
-vi.mock('@/features/waveform/store/waveformRefreshGen', () => ({
+vi.mock('@/store/waveformRefreshGen', () => ({
   getWaveformRefreshGen: hoisted.getGenMock,
 }));
 
-import { refreshWaveformForTrack } from '@/features/waveform/store/waveformRefresh';
+import { refreshWaveformForTrack } from '@/store/waveformRefresh';
 
 beforeEach(() => {
   hoisted.invokeMock.mockReset();

src/store/waveformRefresh.ts

@@ -1,8 +1,8 @@
 import { invoke } from '@tauri-apps/api/core';
-import { coerceWaveformBins } from '@/features/waveform/utils/waveformParse';
+import { coerceWaveformBins } from '@/utils/waveform/waveformParse';
 import { getPlaybackIndexKey } from '@/utils/playback/playbackServer';
 import { usePlayerStore } from '@/store/playerStore';
-import { getWaveformRefreshGen } from '@/features/waveform/store/waveformRefreshGen';
+import { getWaveformRefreshGen } from '@/store/waveformRefreshGen';
 
 /** Subsonic-server waveform-cache row as Rust hands it back. */
 export type WaveformCachePayload = {

src/store/waveformRefreshGen.test.ts

@@ -3,7 +3,7 @@ import {
   _resetWaveformRefreshGenForTest,
   bumpWaveformRefreshGen,
   getWaveformRefreshGen,
-} from '@/features/waveform/store/waveformRefreshGen';
+} from '@/store/waveformRefreshGen';
 
 afterEach(() => {
   _resetWaveformRefreshGenForTest();

src/utils/waveform/waveformParse.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from 'vitest';
-import { coerceWaveformBins, waveformBlobLenOk } from '@/features/waveform/utils/waveformParse';
+import { coerceWaveformBins, waveformBlobLenOk } from '@/utils/waveform/waveformParse';
 
 describe('waveformBlobLenOk', () => {
   it('accepts the legacy single-curve length (500)', () => {