Add a loading icon when query loads on signup page, or make query faster

It takes a second for the train routes query to load. On http://localhost:9000/signup so a loading bar or a faster query would be good.

Start at the signup page at http://localhost:9000/signup and trace the train routes query mentioned in the issue. Determine whether the query or its loading state is the relevant entry point; done means the delay is addressed with a loading indicator or a faster query, as confirmed on the signup page.

Written by the indexing model from the issue text.