circle_member_must_be_realm_member· reason_code· applies to state_resolutionSub-reason for failed_precondition on ak.circle.member.state -> join when, in the accepting cut, the target actor's parent Realm member_state current is not `join` or its typed revision differs from the payload's parent_membership_revision. Circle.members ⊆ Realm.members is a hard invariant bound to the exact current parent join. See zh/models/circle.md §9.1.