Lyrics and karaoke for the music player

- full-screen lyrics view that follows the song: highlighted current line with a colour sweep (word by word when the source has word timing), tap a line to jump, text size, timing nudge, 'Wrong lyrics?' search
- Karaoke mode: the current line large and centered
- lyrics from Plex first, then the bundled Lyrica service (LRCLIB, Musixmatch via Lrcmux, NetEase, Megalobiz); YouTube captions never used; wrong-length recordings refused; answers kept in /data/lyrics
- lyrica/: Lyrica pinned to one commit, built by the workflow as hub-lyrica; compose service sharing the hub's network
- tools/lyrics-test.js

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

Dockerfile

@@ -2,7 +2,7 @@ FROM node:22-alpine
 WORKDIR /app
 COPY package.json package-lock.json ./
 RUN npm ci --omit=dev
-COPY server.js auth.js cal.js ics.js caldav.js tasks.js settings.js search.js users.js admin.js vault.js signal.js ./
+COPY server.js auth.js cal.js ics.js caldav.js tasks.js settings.js search.js users.js admin.js vault.js signal.js lyrics.js ./
 COPY public ./public
 ENV PORT=8080 DATA_DIR=/data
 RUN mkdir -p /data && chown node:node /data