CHW-1204 CannotModifyBroaderMember

the target member holds broader permissions than the caller; ask an equally-or-more privileged admin to make the change

Default message: the target member holds broader permissions than the caller; ask an equally-or-more privileged admin to make the change
HTTP status: 403 (client)

Problem. The caller tried to change the role of, or remove, a member whose existing permissions are broader than theirs. Cause. The RBAC rules forbid a narrower admin from unseating a broader one (e.g. a manager editing an org-admin). Fix. Ask an equally- or more-privileged admin to make the change. HTTP 403.