feat: v1.34.1 — fullscreen lyrics overlay, FsArt crossfade, lyrics toggle, contributor updates

- FullscreenPlayer: synced lyrics overlay (5-line rail, mask fade, click-to-seek)
- FullscreenPlayer: FsArt crossfade component with onLoad pattern, 300px art, next-track pre-fetch
- FullscreenPlayer: MicVocal lyrics toggle button next to heart (persisted in authStore)
- FullscreenPlayer: idle system — only close button auto-hides, cluster+seekbar always visible
- LyricsPane: refactored to use shared useLyrics hook (no double-fetch with FS overlay)
- authStore: showFullscreenLyrics field (default true)
- i18n: fsLyricsToggle key added to all 7 locales; ru2.ts removed (merged into ru.ts)
- Settings: Contributors updated (nisrael, cucadmuh, kilyabin); logout moved to Server tab as btn-danger
- theme.css: btn-danger style added

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/api/subsonic.ts

@@ -606,3 +606,40 @@ export async function getTopRadioStations(offset = 0): Promise<RadioBrowserStati
 export async function fetchUrlBytes(url: string): Promise<[number[], string]> {
   return invoke<[number[], string]>('fetch_url_bytes', { url });
 }
+
+// ─── Structured Lyrics (OpenSubsonic / getLyricsBySongId) ────────────────────
+
+export interface SubsonicLyricLine {
+  start?: number; // milliseconds — absent when unsynced
+  value: string;
+}
+
+export interface SubsonicStructuredLyrics {
+  issynced: boolean;
+  lang?: string;
+  offset?: number;
+  displayArtist?: string;
+  displayTitle?: string;
+  line: SubsonicLyricLine[];
+}
+
+/**
+ * Fetches structured lyrics from the server's embedded tags via the
+ * OpenSubsonic `getLyricsBySongId` endpoint. Returns null when the
+ * server doesn't support the endpoint or the track has no embedded lyrics.
+ * Prefers synced lyrics over plain when both are present.
+ */
+export async function getLyricsBySongId(id: string): Promise<SubsonicStructuredLyrics | null> {
+  try {
+    const data = await api<{ lyricsList: { structuredLyrics?: SubsonicStructuredLyrics[] } }>(
+      'getLyricsBySongId.view',
+      { id },
+    );
+    const list = data.lyricsList?.structuredLyrics;
+    if (!list || list.length === 0) return null;
+    return list.find(l => l.issynced) ?? list[0];
+  } catch {
+    // Server doesn't support the endpoint or track has no embedded lyrics
+    return null;
+  }
+}