TYPE_LABELS_KEY

Reserved key on a Map<String, Any?> blackboard value carrying the flattened ancestor type names (self + parents + grandparents…), used by satisfiesType to match preconditions on parent types. Value is an Iterable<String> of names. Optional — when absent, only TYPE_NAME_KEY is consulted, which means the map only satisfies its own type, not its ancestors. Emitters that know the type's parent chain should populate this so the value behaves like a DomainInstance for inheritance.