using cron to run demo cleanup every day at midnight

lib/services/demoCleanup.js

@@ -1,29 +1,14 @@
-import { setInterval } from 'node:timers';
 import { removeJobsByUserId } from './storage/jobStorage.js';
 import { config } from '../utils.js';
 import { getUsers } from './storage/userStorage.js';
 import logger from './logger.js';
+import cron from 'node-cron';
 
 /**
  * if we are running in demo environment, we have to cleanup the db files (specifically the jobs table)
  */
 export function cleanupDemoAtMidnight() {
-  const now = new Date();
-  const millisUntilMidnightUTC =
-    (24 - now.getUTCHours()) * 60 * 60 * 1000 -
-    now.getUTCMinutes() * 60 * 1000 -
-    now.getUTCSeconds() * 1000 -
-    now.getUTCMilliseconds();
-
-  cleanup();
-  setTimeout(() => {
-    setInterval(
-      () => {
-        cleanup();
-      },
-      24 * 60 * 60 * 1000,
-    );
-  }, millisUntilMidnightUTC);
+  cron.schedule('0 0 * * *', cleanup);
 }
 
 function cleanup() {