feat(api): add unified v2 gateway and mobile read slice

backend/unified-api/src/server.js

@@ -0,0 +1,9 @@
+import { createApp } from './app.js';
+
+const port = Number(process.env.PORT || 8080);
+const app = createApp();
+
+app.listen(port, () => {
+  // eslint-disable-next-line no-console
+  console.log(`krow-api-v2 listening on port ${port}`);
+});