the player moves to the plugin, and src/ has no music code left

officerdev/src/MusicPlayer/ → plugins/music/web/. Engine, state, bar,
favourites, lyrics toggle and the library vocabulary — ten files. The barrel
stops exporting a player it no longer has, and DashboardLayout stops rendering
one.

The reasoning that kept it was removed rather than refuted. It stayed because
the dashboard widget imported useMusicPlayer from officerdev and the platform
cannot import from a plugin, so the state had to stay whatever was decided
about the UI. The owner moved the widget into the plugin in the previous
commit, and the constraint went with it: the whole remaining dependency became
one line, DashboardLayout.tsx:66.

MusicPlayerHost is mounted inside the MusicDetail panel. That reads odd until
you notice it already returned null on /music — the mini bar is the transport
there, and the host existed purely to own the GaplessEngine. In the panel it
does exactly that, and the bar code stays intact for whenever there is a slot.

[phase 2] Leaving /music unmounts the host and playback stops. Deferred on the
owner's call; the bar was "navigating away must not break the application", and
that holds: seekPlayer is optional-chained so a call with no host registered is
a no-op, registerPlayerSeek clears only its own registration, the host's
cleanup destroys the engine and nulls its ref, and the queue is global state so
returning to /music remounts and reloads. Solving it properly needs either a
shell slot a plugin can contribute to — which reopens "there is no way to
export a component" — or the engine hoisted to module scope, which keeps the
rule and loses only the off-route controls.

Also: the parked widget now imports the player as a sibling rather than through
officerdev, and shared.ts stopped being a re-export shim now that the real file
is in the plugin.

Verified: tsgo clean, 797 tests / 787 pass / same 7. Server restarts, mounts
/example /music /offscale, / and /music both 200, and the player is in the
built bundle (music.volume, music:lyrics, now-playing?device=web all present —
GaplessEngine is a class name and the production build is minified, so grepping
for it proves nothing).

Not verified by me: what it looks like in a browser. That needs your eyes.

plugins/music/web/MusicDetail.tsx

@@ -6,13 +6,14 @@ import { usePanelChannel } from 'hooks/usePanelChannel';
 import { Play, Pause, ChevronLeft, MicVocal, Volume2 } from 'lucide-react';
 import type { LayoutNode, PanelComponents } from 'officerdev';
 import { WorkspaceLayout } from 'officerdev';
-import { MusicHeart } from 'officerdev';
+import { MusicHeart } from './MusicHeart';
 import { FavoritesView } from './FavoritesView';
-import { useMusicPlayer } from 'officerdev';
-import type { PlayerTrack } from 'officerdev';
+import { useMusicPlayer } from './useMusicPlayer';
+import type { PlayerTrack } from './useMusicPlayer';
 import { LyricsPanel } from './LyricsPanel';
 import { MusicMiniBar } from './MusicMiniBar';
-import { useLyricsOpen } from 'officerdev';
+import { MusicPlayerHost } from './MusicPlayerHost';
+import { useLyricsOpen } from './useLyricsOpen';
 import {
   MUSIC_ROOT,
   MUSIC_FAV_CHANNEL,
@@ -414,6 +415,16 @@ export const MusicDetail = () => {
     <div className="flex h-full flex-col">
       {content}
       <MusicMiniBar />
+      {/* The audio engine, mounted HERE rather than by the shell.
+          It moved out of DashboardLayout on 2026-08-15 when the player became the plugin's. It renders
+          nothing while the route is /music — the mini bar above is the transport — so this is purely
+          "something owns the GaplessEngine while the screen is open".
+          [phase 2] Leaving /music unmounts it, which stops playback. Making audio outlive the route
+          needs either a shell slot a plugin can contribute to, or the engine hoisted to module scope;
+          that decision is deliberately deferred. Nothing breaks in the meantime: player-time's
+          registrations are optional-chained and the queue lives in global state, so returning to /music
+          remounts the host and reloads it. */}
+      <MusicPlayerHost />
     </div>
   );