fix(totp): delete user TOTP key after disabling the provider

[sjinks]

What?

The REST handler deletes the TOTP secret key first (delete_user_totp_key()), then attempts to disable the provider via Two_Factor_Core::disable_provider_for_user(). If disabling fails (due to a DB error), the request returns an error, but the secret has already been removed.

Why?

Inconsistent user state: the provider may remain enabled even when no secret exists, potentially causing login failures or confusing the UI.

How?

Change operation order: disable the provider first.

Testing Instructions

N/A

Screenshots or screencast

N/A

Changelog Entry

Fixed - delete user TOTP key only after the provider has been successfully disabled.

[github-actions]

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[masteradhoc]

In the old flow, if disable_provider_for_user() failed for any reason, you had already deleted the key. Looks good to not destroy the totp until the provider disable actually succeeds.

[georgestephanis]

Sounds good -- I'm wondering if it would be worth seperating the deletions though, so you can temporarily disable totp without purging the key entirely so it could be reenabled with existing authenticators?