chore: Apply rate limiter to all requests in server.js (#6)

ai/copilot/contoso-real-state-plugin/server.js

@@ -5,6 +5,16 @@ import cors from "cors";
 
 const app = express();
 
+// set up rate limiter: maximum of five requests per minute
+var RateLimit = require('express-rate-limit');
+var limiter = RateLimit({
+  windowMs: 15 * 60 * 1000, // 15 minutes
+  max: 100, // max 100 requests per windowMs
+});
+
+// apply rate limiter to all requests
+app.use(limiter);
+
 //add logging to app
 app.use((req, res, next) => {
     console.log(`${req.method} request for ${req.url}`);