Changing user email address does not trigger any re-verification

### Current Behavior

A user can edit their email via User Settings, but it does not prompt any re-verification.

### Expected Behavior

Changing a user's email address should trigger re-verification.

There are practical questions about what we should do here to help prevent a user locking themselves out. If they typo the email address they have no way to fix the mistake as we then require them to click the link in an email they cannot receive.

We may want to relax what an existing user can do until they reverify - rather than block their access entirely as we do today. For example, add a notification to the page asking them to reverify, but still allow them to continue using the platform.

### Steps To Reproduce

Change your email address.

Observe no attempt is made to reverify and that the Admin view shows the user still has a verified email.

### Environment

- FlowForge version:
- Node.js version:
- npm version:
- Platform/OS:
- Browser: