SSO — Payload CMS plugins 5

Adds Keycloak single sign-on to Payload CMS 3 via an OIDC auth strategy with PKCE, silent token refresh, and permission-based access control.

Adds Google and Microsoft (Entra ID) OAuth social login buttons to the Payload admin panel and authenticated collections.

Authenticate users with SSO and cookies in Payload CMS.

Integrates Auth0 authentication with Payload CMS.

Adds Google One Tap sign-in to the Payload admin login page using OAuth credentials.