feat: add cron cleanup and worker-check scripts

worker/cron-check.ts

@@ -0,0 +1,40 @@
+import { existsSync, readFileSync, writeFileSync } from 'fs'
+import { spawn } from 'child_process'
+import path from 'path'
+
+const PID_FILE = path.join(__dirname, 'worker.pid')
+
+function isRunning(pid: number): boolean {
+  try {
+    process.kill(pid, 0)
+    return true
+  } catch {
+    return false
+  }
+}
+
+if (existsSync(PID_FILE)) {
+  const pid = parseInt(readFileSync(PID_FILE, 'utf-8').trim(), 10)
+  if (!isNaN(pid) && isRunning(pid)) {
+    console.log(`[cron-check] worker already running (PID ${pid})`)
+    process.exit(0)
+  }
+}
+
+const child = spawn(
+  'node',
+  [
+    '-r', 'ts-node/register',
+    '-r', 'tsconfig-paths/register',
+    path.join(__dirname, 'index.ts'),
+  ],
+  { detached: true, stdio: 'ignore' }
+)
+child.unref()
+
+if (child.pid) {
+  writeFileSync(PID_FILE, String(child.pid))
+  console.log(`[cron-check] worker started (PID ${child.pid})`)
+}
+
+process.exit(0)