frontend: Fetch types/enums from backend

Is it possible somehow to get these enums from the backend ? To avoid maintaining two enums in sync.

_Originally posted by @patrickelectric in https://github.com/bluerobotics/companion-docker/pull/439#discussion_r699533676_

We should study the possibility of having the types and enums declared only on the backend, so the frontend can just fetch it and have it in sync.

I suspect we will have problems with type-check and auto-complete, though, since this would be dynamically loaded.