feat: add AI catalog description generation

backend/test/catalog-operation-coordinator.test.ts

@@ -18,3 +18,23 @@ test("reserves duplicate database ids only once for a batch operation", async ()
   expect(await coordinator.runMany(["database-a", "database-a"], async () => "completed"))
     .toBe("completed");
 });
+
+test("stale generation recovery releases only its own reservation token", () => {
+  const coordinator = new CatalogOperationCoordinator();
+  const releaseOtherOperation = coordinator.reserve("database-a");
+
+  coordinator.releaseStale("database-a", "description_generation");
+  expect(() => coordinator.reserve("database-a")).toThrow(
+    "A database operation is already in progress",
+  );
+  releaseOtherOperation();
+
+  const releaseStaleGeneration = coordinator.reserve("database-a", "description_generation");
+  coordinator.releaseStale("database-a", "description_generation");
+  const releaseNewOperation = coordinator.reserve("database-a");
+  releaseStaleGeneration();
+  expect(() => coordinator.reserve("database-a")).toThrow(
+    "A database operation is already in progress",
+  );
+  releaseNewOperation();
+});