Bug fix
IUserManager.RenameUser exists in the Jellyfin 10.11.3 NuGet package the plugin is compiled against, but was removed in Jellyfin 10.11.10. When Sync display name from OIDC token was enabled, any login attempt would crash with MissingMethodException.
Fix: Set user.Username directly and call UpdateUserAsync — the same underlying operation RenameUser performed. If the update fails (e.g. name collision), the original name is restored and a warning is logged without blocking login.
Full Changelog: v1.0.2.3...v1.0.2.4