feat(hierarchy): audit event + outbox machinery (M4-1b-i, contract 1 §5.2) (#1460)

apps/gateway/src/hierarchy/hierarchy.module.ts

@@ -0,0 +1,17 @@
+import { Module } from '@nestjs/common';
+import { HierarchyAuditRepository } from './hierarchy-audit.repository.js';
+
+/**
+ * Hierarchy (tenancy/authorization structure) feature module.
+ *
+ * M4-1b-i ships the audit event + outbox machinery only (contract 1 §5.2).
+ * The hierarchy command family — controllers, DTOs, and the allowlisted
+ * class-table repositories — lands in M4-1b-ii once contract 2 (RBAC grant
+ * model) merges; until then this module exposes no routes, which the
+ * route-inventory witness asserts.
+ */
+@Module({
+  providers: [HierarchyAuditRepository],
+  exports: [HierarchyAuditRepository],
+})
+export class HierarchyModule {}