Add IDashboardSessionAdminService (Admin-role gate, friendly errors,
audit logging) wrapping a new ISessionManager.KillWorkerAsync that
skips graceful shutdown and cleans up registry/metrics. Sessions,
Workers, and SessionDetails pages render Close / Kill buttons only
when CanManage; the service re-checks the role on every call so
forged clicks return Unauthenticated.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Joseph Doherty