Add environment variables

Add environment variables

⚠️ If you haven't read the Getting started - Configuration section, you should start with it

Environment variables are made available into the app through the appConfig file.

To add a new one :

1. Add it into the appConfig
2. Add it into your docker-compose, to correctly forward it when running docker-compose up
3. Give it a default value in your .envrc
4. Reload your .envrc (direnv allow or source .envrc)