Remove express

[DiegoRBaquero]

L1 doesn't need a full web framework. Express should be removed.

[juliangruber]

I personally like using little wrappers like https://github.com/electron/update.electronjs.org/blob/f0d89fe197ed13b63fbe58af96492eab1b4c21cc/index.js#L42-L60, which help with error responses and request logging

[juliangruber]

Instead of going frameworkless, @bajtos suggested looking at fastify

[juliangruber]

Should we not remove express, we must secure the current async route handlers, which aren't supported natively by the framework. @guanzo suggested using https://www.npmjs.com/package/express-async-errors in this case.