invite_event_actor_mismatch· reason_code· applies to service_callSub-reason for failed_precondition when ak.self.invites.command.dispatch.v1 resolves invite_event_id to an accepted Event whose signing actor is not the authenticated session actor. The request carries only the Event ID; the service MUST NOT co-sign or re-author the resolved Event; see zh/sync/invite-addressing.md §7.