Add super admin user management

backend/server.js

@@ -7,6 +7,7 @@ const stockRoutes = require('./routes/stockRoutes');
 const campaignRoutes = require('./routes/campaignRoutes');
 const internalRoutes = require('./routes/internalRoutes');
 const analyticsRoutes = require('./routes/analyticsRoutes');
+const userRoutes = require('./routes/userRoutes');
 
 const createApp = () => {
     const app = express();
@@ -19,8 +20,25 @@ const createApp = () => {
     app.use('/api', stockRoutes);
     app.use('/api', campaignRoutes);
     app.use('/api', analyticsRoutes);
+    app.use('/api', userRoutes);
     app.use('/api/internal', internalRoutes);
 
+    app.use((err, req, res, next) => {
+        if (res.headersSent) {
+            next(err);
+            return;
+        }
+
+        const statusCode = err.statusCode || 500;
+        if (statusCode >= 500) {
+            console.error(err);
+        }
+
+        res.status(statusCode).json({
+            error: err.message || 'Internal server error'
+        });
+    });
+
     return app;
 };