make email address editable

[zven]

Description

At the moment, I can't edit my email address once I've signed up. The email address should be editable in the settings:

When I have entered a new email address, I should also get a new account verification email, the new email address should marked as not verified in the settings menu.

Open question:

• Should any functions be locked as long as I have not verified the new email address?

Use case

• Typo on signup: Image I have signed up and accidentaly miss-typed my email address. I want to change it in the settings so that I can actually receive an account verification email
• My email address has changed and I want to update my osem account.

Implementation ideas (optional)

We still have an old settings menu in the code account.settings.tsx that is still reachable via account/settings. Since this is code duplication, we should kick it out!

Additional information (optional)

No response