[arnaudfnr]

What this PR does :

• Update backend Dockerfile following the Docker Docs here : https://docs.docker.com/guides/django/
• Unfortunately could not use DHI images but I used python trixie image, better than Alpine
• Django backend server is now started using gunicorn, which is optimized for production use
• Backend now uses UV to sync packages, was nicer to use with docker and closer to docker doc
• Use a secure DJANGO SECRET KEY (defined in environment)
• Data catalog, that contains parquet files, is now persisted as a volume to prevent data loss, and is generated during docker build, not when container is started, thus there is no delay between the deployment and the start to use the app.
• Update coordo to 0.14.1 with a bugfix
• Webapp (frontend) dockerfile now uses a develoment stage in main Dockerfile instead of two Dockerfile.dev for develoment builds