Part of [ENG-5153](https://linear.app/comm/issue/ENG-5153)
Depends on D9397
We would like to separate hosting web app on dev environment to `localhost:3000/webapp/`` and move the keyserver logic to `localhost:3000/keyserver/` (so in the end nothing will be hosted on `localhost:3000/`) to simplify the dev environment and allow for web <-> keyserver separation. We can also use this opportunity to cleanup the naming. This diff automatically adds new files on nix start. They will be used in the later diff.
Production will need to be updated so that `keyserver_url.json` contains data from `squadcal_url.json` and `webapp_url.json` contains data from `commapp_url.json`