[Hardening] F-02: Default Configuration Forces User’s Posture to Password-Only.

### The required feature described as a wish

**Description:** the global configuration setting `enable.user.2fa` defaults to False, meaning users who wish to use two-factor authentication (2FA) cannot do so without a Root Admin first enabling the setting and restarting the management server(s).

**Affected Components:** Management UI

**Impact:** Any compromised or weak user credential is sufficient to gain full access to a user's CloudStack account. This makes the platform susceptible to credential-stuffing, phishing, and brute-force attacks with no second factor to impede unauthorized access.

**Steps to Reproduce:**
- Log in to the CloudStack Management UI as a Root Admin.
- Navigate to Configuration > Global Settings.
- Search for `enable.user.2fa` and observe that its value is set to False.
- Attempt to enable 2FA on your own user account, and confirm that it is not permitted.

**Recommended Remediation:** Change the default value of `enable.user.2fa` to True so that users are always permitted to enroll in 2FA without requiring Root Admin intervention.

Beginne in der Management UI mit der Verarbeitung von enable.user.2fa in den Global Settings und prüfe, wie dessen Standardwert die Benutzerregistrierung steuert. Die Änderung ist abgeschlossen, wenn der Standardwert Benutzern ermöglicht, sich ohne Eingreifen eines Root Admin oder Neustart des management-server für 2FA zu registrieren; bestätige die Einstellung und den Registrierungsablauf in der UI.

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