Add Spotify lyrics sidecar service and integrate with prefetch

- Add spotify-lyrics-api container to docker-compose
- Update SpotifyLyricsService to use sidecar API
- Prefetch now tries Spotify lyrics first (using track ID), then LRCLib
- Add SPOTIFY_LYRICS_API_URL setting
- Sidecar handles sp_dc cookie authentication automatically

docker-compose.yml

@@ -17,6 +17,23 @@ services:
     networks:
       - allstarr-network
 
+  spotify-lyrics:
+    image: akashrchandran/spotify-lyrics-api:latest
+    container_name: allstarr-spotify-lyrics
+    restart: unless-stopped
+    # Only accessible internally - no external port exposure
+    expose:
+      - "8080"
+    environment:
+      - SP_DC=${SPOTIFY_API_SESSION_COOKIE:-}
+    networks:
+      - allstarr-network
+    healthcheck:
+      test: ["CMD", "wget", "--spider", "-q", "http://localhost:8080/"]
+      interval: 30s
+      timeout: 5s
+      retries: 3
+
   allstarr:
     # Use pre-built image from GitHub Container Registry
     # For latest stable: ghcr.io/sopat712/allstarr:latest
@@ -40,6 +57,8 @@ services:
     depends_on:
       redis:
         condition: service_healthy
+      spotify-lyrics:
+        condition: service_started
     healthcheck:
       test: ["CMD", "curl", "-f", "http://localhost:8080/health"]
       interval: 30s
@@ -98,6 +117,8 @@ services:
       - SpotifyApi__CacheDurationMinutes=${SPOTIFY_API_CACHE_DURATION_MINUTES:-60}
       - SpotifyApi__RateLimitDelayMs=${SPOTIFY_API_RATE_LIMIT_DELAY_MS:-100}
       - SpotifyApi__PreferIsrcMatching=${SPOTIFY_API_PREFER_ISRC_MATCHING:-true}
+      # Spotify Lyrics API sidecar service URL (internal)
+      - SpotifyApi__LyricsApiUrl=${SPOTIFY_LYRICS_API_URL:-http://spotify-lyrics:8080}
       
       # ===== SHARED =====
       - Library__DownloadPath=/app/downloads