restore node-cron + cron jobs

backend/package.json

@@ -11,7 +11,8 @@
   "dependencies": {
     "cors": "^2.8.5",
     "dotenv": "^17.2.0",
-    "express": "^5.1.0"
+    "express": "^5.1.0",
+    "node-cron": "^4.5.0"
   },
   "devDependencies": {
     "@types/cors": "^2.8.19",

backend/src/index.ts

@@ -2,6 +2,7 @@ import 'dotenv/config';
 import path from 'path';
 import { fileURLToPath } from 'url';
 import cors from 'cors';
+import cron from 'node-cron';
 import express, { type NextFunction, type Request, type Response } from 'express';
 import { buildApiPath, getConfig } from './config';
 import { TursoClient } from './lib/db';
@@ -22,6 +23,14 @@ const apiRoot = config.apiPrefix || '/';
 app.use(apiRoot, createHealthRouter(config));
 app.use(apiRoot, createTodosRouter(config, db));
 
+cron.schedule('*/3 * * * *', () => {
+  console.log('[Cron A] Heartbeat executing every 3 minutes: ' + new Date().toISOString());
+});
+
+cron.schedule('*/10 * * * *', () => {
+  console.log('[Cron B] Heartbeat executing every 10 minutes: ' + new Date().toISOString());
+});
+
 app.post('/_cron/tick', (req, res) => {
   const token = req.headers.authorization?.replace(/^Bearer\s+/i, '') || '';
   const expected = process.env.CRON_TOKEN || '';
@@ -29,7 +38,8 @@ app.post('/_cron/tick', (req, res) => {
     res.status(401).json({ success: false, error: 'Invalid cron token' });
     return;
   }
-  res.status(200).json({ success: true, ticked: new Date().toISOString() });
+  console.log('[Tick] Heartbeat received. Waking up event loop.');
+  res.status(200).json({ success: true });
 });
 
 const publicDir = path.join(__dirname, '../public');