Use YubiKey as MFA factor on Desktop Client

As a Defguard user, I want to register and use my YubiKey as a multi-factor authentication method, so that I can secure my account with a phishing-resistant hardware factor.

**Acceptance criteria:**

1. A user can enroll a YubiKey from their profile, and assign it a friendly name.
2. A user can register more than one security key (e.g., a primary and a backup).
3. During login, when MFA is required, the user is prompted to touch their YubiKey; successful assertion completes authentication.
5. A user can view, rename, and delete registered keys from their profile.