fix(playback): pin queue playback to source server when browsing another library (#717)

* fix(playback): pin queue streams, cover art, and library links to queue server

When the active server changes while a queue from another server is playing,
keep streams and UI on queueServerId; switch back for artist/album links and
queue or player-bar context menus.

* fix(playback): switch to queue server when opening Now Playing

Ensure active server matches queueServerId before Subsonic fetches on the
Now Playing page, mobile player route, and queue info panel; scope caches
by server id.

* docs(credits): mention Now Playing in PR #717 contribution line

* fix(playback): route scrobble and queue sync to queue server

Address PR review: apiForServer for scrobble/now-playing/savePlayQueue,
clear queueServerId on server removal, mini-player queueServerId sync,
block cross-server enqueue with toast, and regression tests.

src/store/authServerProfileActions.ts

@@ -1,5 +1,7 @@
 import type { AuthState } from './authStoreTypes';
 import { generateId } from './authStoreHelpers';
+import { usePlayerStore } from './playerStore';
+import { clearQueueServerForPlayback } from '../utils/playback/playbackServer';
 
 type SetState = (
   partial: Partial<AuthState> | ((state: AuthState) => Partial<AuthState>),
@@ -38,6 +40,9 @@ export function createServerProfileActions(set: SetState): Pick<
     },
 
     removeServer: (id) => {
+      if (usePlayerStore.getState().queueServerId === id) {
+        clearQueueServerForPlayback();
+      }
       set(s => {
         const newServers = s.servers.filter(srv => srv.id !== id);
         const switchedAway = s.activeServerId === id;