fix(player): show live track metadata, not the stale queue snapshot

The queue slice stores denormalized display fields captured at play-time, so the
player and queue panel kept showing pre-enrichment title/artist after a track's
metadata was updated — the library (RTKQ cache) and the player disagreed.

Add useResolvedQueueEntry: read through to the RTKQ Track cache and prefer its
fresh values, keeping the snapshot only as instant/offline fallback. Wire it into
PersistentPlayer (now-playing + cover) and QueuePanel (now-playing + up-next
rows), so enrichment updates reach the player through the same Track tags that
refresh the library.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/hooks/useResolvedQueueEntry.ts

@@ -0,0 +1,37 @@
+import { skipToken } from '@reduxjs/toolkit/query';
+import { useGetTrackQuery } from '../api/endpoints/library';
+import type { QueueEntry } from '../store/slices/queue';
+
+export interface ResolvedQueueEntry {
+  trackId: string;
+  title: string;
+  artistName: string;
+  albumTitle: string;
+  durationMs: number;
+  hasCover: boolean;
+}
+
+/**
+ * Merge a queue entry's play-time snapshot with the live `Track` cache.
+ *
+ * The queue slice stores denormalized display fields (title/artist/…) captured
+ * when a track was queued, so they go stale after metadata enrichment updates
+ * the track. This reads through to the RTKQ `Track` cache — invalidated by the
+ * same tags that refresh the library — and prefers its fresh values, falling
+ * back to the snapshot for instant render and offline. Returns undefined when
+ * there is no current entry.
+ */
+export function useResolvedQueueEntry(
+  entry: QueueEntry | undefined,
+): ResolvedQueueEntry | undefined {
+  const { data } = useGetTrackQuery(entry?.trackId ?? skipToken);
+  if (!entry) return undefined;
+  return {
+    trackId: entry.trackId,
+    title: data?.title ?? entry.title,
+    artistName: data?.artistName ?? entry.artistName,
+    albumTitle: data?.albumTitle ?? entry.albumTitle,
+    durationMs: data?.durationMs ?? entry.durationMs,
+    hasCover: data?.hasCover ?? false,
+  };
+}