Launch Command Env Vars

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When you run the launch command, Wasp CLI knows how to connect different parts of your Wasp app together, so it sets up the required environment variables for your server app:

1. WASP_WEB_CLIENT_URL and WASP_SERVER_URL which are required to connect your client and server apps.
2. DATABASE_URL which is required to connect your server app to the database.
3. JWT_SECRET which is required for authentication to work.