jmgimeno/code-to-screen-scala ? reverse-engineered prompt

Build me a simple full stack web app called code to screen that has a Scala backend and a Scala.js frontend, with the frontend built as a small single page app and connected to the backend with websockets. I want to be able to type a message in the browser and send it to the server, then see the message come back or show up in the browser so I know the connection is working.

Make it easy to run in development with live reloading if possible, and set it up so the frontend and backend can be started separately. If you need to check the latest docs for any Scala.js or websocket details, go ahead and look them up online.

Also make it something I can build into a single runnable app for production, with a Docker option too. Keep the UI very minimal and clean, just enough to prove the app works.