Verify page should be interactive

[elboletaire]

Right now the verify page can only be accessed with the params defined in the URL. This page should show a form to allow manually adding the values in case they're not received in the URL.

Also, a "re-send code" button should be added for the required use cases.

This is required since some part of the invite flow relies on being able to access this URL without knowing the required URL params (see #828)

Edit: Actually, we currently have two different verification components:

• One accessible via /account/verify, which is not interactive at all
• Another one only loaded embedded in /account/signup, which shows a form to add the code.

I think we should unify them both, and use the embedded one as the default, since it already has the fields shown. The difference should be: if no params are provided, show the form. If params are provided, show the form too, but disabled and it should instantly show the button as loading because it's making the required calls.

Remember to also handle the "last verification code still valid" error in this revamp.