Refactor logging implementation and enhance authentication logging

middleware/auth.js

@@ -1,10 +1,12 @@
 const basicAuth = require('basic-auth');
+const logger = require('../logger');
 
 const auth = (req, res, next) => {
     if (req.session && req.session.user) {
         return next();
     } else {
         res.status(401).send('Authentication required.');
+        logger.error('Unauthorized access attempted from IP:', req.ip);
     }
 };