Microsoft Entra ID never sends email_verified, so existing accounts could
not be linked through OIDC. Treat a boolean true xms_edov claim (email
domain owner verified) as equivalent, via a shared
OidcUser::claimsVerifyEmail() helper used for both ID token and userinfo
claims.
Document the Entra ID issuer URL and required optional claims in the
OIDC settings helper text, and add tests covering xms_edov handling.
Add OIDC discovery, JWKS validation, Socialite integration, OAuth identity linking, and configurable registration policy for password and SSO signups. Update related settings/profile UI and tests.