Add Docker support with Dockerfile, docker-compose, and deployment documentation

docker-compose.yml

@@ -0,0 +1,25 @@
+version: '3.8'
+
+services:
+  carplay-audio:
+    build: .
+    container_name: carplay-audio-server
+    restart: unless-stopped
+    ports:
+      - "4000:4000"
+    volumes:
+      # Mount your music library (change the left path to your music folder)
+      - /Volumes/Data/Music:/data/music:ro
+      # Persistent data (database, artwork, config)
+      - ./data/artwork:/app/artwork
+      - ./data/database:/app
+      - ./config.json:/app/config.json
+    environment:
+      - NODE_ENV=production
+      - PORT=4000
+    healthcheck:
+      test: ["CMD", "wget", "--quiet", "--tries=1", "--spider", "http://localhost:4000/health"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+      start_period: 40s