[ENHANCEMENT] Verify 2FA after it's activated

[bobhenl]

Describe the feature you'd like to have implemented
I'd like to suggest that players should verify that they scanned 2FA codes by verifying it. So after they activate 2FA using
`/2fa enable , they should be prompted to enter the code that the Authenticator app gave them after scanning the QR code.

Is your feature request related to an existing problem? Please describe.
Players usually activate it & they don't know they need to scan the QR code & they just want it reset. There's also no /2fa reset command, like /force2fareset that would be useful, as well in this case.

Additional context
Almost any websites & applications prompt you to verify the 2FA after you scanned the code, otherwise do not activate it.