add backend hatchet worker for calendar predue sync

backend_worker/src/hatchet/worker.ts

@@ -0,0 +1,22 @@
+import { hatchet } from "./client";
+import { backendCalendarTimelineScheduler } from "./workflow";
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+
+async function main() {
+  const worker = await hatchet.worker("backend-worker", {
+    workflows: [backendCalendarTimelineScheduler],
+  });
+
+  await worker.start();
+}
+
+const isMain = process.argv[1] && path.resolve(process.argv[1]) === fileURLToPath(import.meta.url);
+
+if (isMain) {
+  main().catch((error) => {
+    const message = error instanceof Error ? error.stack || error.message : String(error);
+    console.error(`[backend_worker/hatchet] worker failed: ${message}`);
+    process.exitCode = 1;
+  });
+}