Add support for TypeScript in the editor (as well for compilation)

[NullVoxPopuli]

This will require figuring out how to add ts_ls in codemirror. The babel/compilation side of this is the easy part 🙈

In particular, it's possible that each framework integration may need to supply their own "how to compile TS", since frameworks like Svelte, Vue, and Ember (and eventually Angular) don't use TSX