codigo refactorizado y ordenado, listo para siguiente fase

node-api/src/app.js

@@ -0,0 +1,29 @@
+import express from 'express';
+import morgan from 'morgan';
+import path from 'path';
+import { fileURLToPath } from 'url';
+import apiRouter from './routes/api.js';
+import radiusRouter from './routes/radius.js';
+
+export function createApp() {
+  const app = express();
+  app.use(express.json());
+  app.use(morgan('dev'));
+
+  const __filename = fileURLToPath(import.meta.url);
+  const __dirname = path.dirname(__filename);
+  app.use(express.static(path.join(__dirname, '..', 'public')));
+
+  // RADIUS hooks (rlm_rest)
+  app.use('/', radiusRouter);
+
+  // REST API
+  app.use('/api', apiRouter);
+
+  app.get('/', (_req, res) => {
+    res.sendFile(path.join(__dirname, '..', 'public', 'index.html'));
+  });
+
+  return app;
+}
+