Add production setup and update Docker configurations

- Introduced a new docker-compose.prod.yml for production deployment.
- Updated docker-compose.yml to change backend port mapping.
- Added svelte-sonner dependency to frontend package.json.
- Created Dockerfile.prod for building the frontend application.
- Enhanced README.md with production deployment instructions.

docker-compose.yml

@@ -162,7 +162,7 @@ services:
       - KEYCLOAK_CLIENT_SECRET=${KEYCLOAK_CLIENT_SECRET:-dev-secret}
       - CORS_ORIGINS=${CORS_ORIGINS:-http://localhost:5173,http://localhost:3000}
     ports:
-      - "5050:8000"
+      - "8000:8000"
     depends_on:
       postgres-a76:
         condition: service_healthy