fix(notifications): replace Cloud Run job with worker service

backend/command-api/src/worker-app.js

@@ -0,0 +1,46 @@
+import express from 'express';
+import pino from 'pino';
+import pinoHttp from 'pino-http';
+
+const logger = pino({ level: process.env.LOG_LEVEL || 'info' });
+
+export function createWorkerApp({ dispatch = async () => ({}) } = {}) {
+  const app = express();
+
+  app.use(
+    pinoHttp({
+      logger,
+    })
+  );
+  app.use(express.json({ limit: '256kb' }));
+
+  app.get('/health', (_req, res) => {
+    res.status(200).json({ ok: true, service: 'notification-worker-v2' });
+  });
+
+  app.get('/readyz', (_req, res) => {
+    res.status(200).json({ ok: true, service: 'notification-worker-v2' });
+  });
+
+  app.post('/tasks/dispatch-notifications', async (req, res) => {
+    try {
+      const summary = await dispatch();
+      res.status(200).json({ ok: true, summary });
+    } catch (error) {
+      req.log?.error?.({ err: error }, 'notification dispatch failed');
+      res.status(500).json({
+        ok: false,
+        error: error?.message || String(error),
+      });
+    }
+  });
+
+  app.use((_req, res) => {
+    res.status(404).json({
+      code: 'NOT_FOUND',
+      message: 'Route not found',
+    });
+  });
+
+  return app;
+}