chore: update docker compose file

- Update compose.yaml to pull policy: always for production environment
- Added RAILS_ENV environment variable for production

Changes impact the overall system functionality by ensuring containers are always pulled from the latest images, and provide clear environment variables for the production environment.

compose.yaml

@@ -3,6 +3,7 @@ services:
     image: songtianlun/today_ai_weather:latest
     #ports:
     #  - "3000:3000"
+    pull_policy: always
     environment:
       - RAILS_ENV=production
       - DATABASE_URL=postgresql://postgres:${PG_PASSWORD}@db:5432/db