feat(ratings): Subsonic entity ratings and StarRating UX

Probe OpenSubsonic after connect; persist album/artist ratings via setRating when supported. Add shared StarRating (repeat same star to clear, pulse and shrink animations, hover freeze after clear). Widen tracklist duration column and bump narrow saved widths in localStorage. Use StarRating in AlbumHeader, track lists, and playlist rows.

src/api/subsonic.ts

@@ -64,6 +64,8 @@ export interface SubsonicAlbum {
   starred?: string;
   recordLabel?: string;
   created?: string;
+  /** Present on some servers (e.g. OpenSubsonic) for album-level rating. */
+  userRating?: number;
 }
 
 export interface SubsonicSong {
@@ -141,6 +143,8 @@ export interface SubsonicArtist {
   albumCount?: number;
   coverArt?: string;
   starred?: string;
+  /** Present on some servers (e.g. OpenSubsonic) for artist-level rating. */
+  userRating?: number;
 }
 
 export interface SubsonicGenre {
@@ -374,6 +378,28 @@ export async function setRating(id: string, rating: number): Promise<void> {
   await api('setRating.view', { id, rating });
 }
 
+/** How aggressively we assume `setRating` accepts album/artist ids (OpenSubsonic-style). */
+export type EntityRatingSupportLevel = 'track_only' | 'full';
+
+/**
+ * Probe server for OpenSubsonic extensions. When `openSubsonic: true`, we treat album/artist
+ * rating as supported (same `setRating.view` + entity id); otherwise track-only.
+ */
+export async function probeEntityRatingSupport(): Promise<EntityRatingSupportLevel> {
+  try {
+    const data = await api<{ openSubsonic?: boolean; openSubsonicExtensions?: unknown[] }>(
+      'getOpenSubsonicExtensions.view',
+      {},
+      8000,
+    );
+    if (data.openSubsonic === true) return 'full';
+    if (Array.isArray(data.openSubsonicExtensions)) return 'full';
+    return 'track_only';
+  } catch {
+    return 'track_only';
+  }
+}
+
 export async function scrobbleSong(id: string, time: number): Promise<void> {
   try {
     await api('scrobble.view', { id, time, submission: true });