`[2026-06-16]` **agent_self → make it CANONICAL (operator decided A).** bifrost's reference lattice was `{end_user, group, tenant}` only (agent_self → `invalid_filter` 400); Worldtree emits agent_self (#248). Operator chose canonical-not-re-expressed; worldtree-dev filed the lattice-addition with bifrost-dev. Implication: our store's permissive axis-acceptance becomes CORRECT once bifrost adds agent_self.