Add production deployment config, Alembic migration, switch to Haiku

- Production Docker Compose with Caddy reverse proxy, Gunicorn, Nginx
- Multi-stage frontend build for production
- Deploy script and automated database backup script
- Initial Alembic migration with all tables
- Switch recommendation model from Sonnet to Haiku for cost efficiency

docker-compose.prod.yml

@@ -0,0 +1,51 @@
+services:
+  db:
+    image: postgres:16-alpine
+    environment:
+      POSTGRES_USER: vynl
+      POSTGRES_PASSWORD: ${DB_PASSWORD}
+      POSTGRES_DB: vynl
+    volumes:
+      - pgdata:/var/lib/postgresql/data
+    restart: unless-stopped
+
+  redis:
+    image: redis:7-alpine
+    restart: unless-stopped
+
+  backend:
+    build:
+      context: ./backend
+      dockerfile: Dockerfile.prod
+    env_file: ./backend/.env
+    depends_on:
+      - db
+      - redis
+    restart: unless-stopped
+
+  frontend:
+    build:
+      context: ./frontend
+      dockerfile: Dockerfile.prod
+      args:
+        VITE_API_URL: ${VITE_API_URL:-}
+    restart: unless-stopped
+
+  caddy:
+    image: caddy:2-alpine
+    ports:
+      - "80:80"
+      - "443:443"
+    volumes:
+      - ./Caddyfile:/etc/caddy/Caddyfile
+      - caddy_data:/data
+      - caddy_config:/config
+    depends_on:
+      - backend
+      - frontend
+    restart: unless-stopped
+
+volumes:
+  pgdata:
+  caddy_data:
+  caddy_config: