removed the default secret key

app/api/routes/user.js

@@ -30,7 +30,7 @@ router.post("/login", (req, res) => {
       const isMatch = await bcrypt.compare(password, user.password);
       
       if (isMatch) {
-        let jwtSecretKey = process.env.JWT_SECRET_KEY || "defaultSecretKey";
+        let jwtSecretKey = process.env.JWT_SECRET_KEY;
         let data = { userId: user.id, username: user.username };
         // Create JWT token
         const token = jwt.sign(data, jwtSecretKey, { expiresIn: "1d" });

app/middlewares/authMiddleware.js

@@ -12,7 +12,7 @@ const verifyToken = (req, res, next) => {
   }
 
   try {
-    const jwtSecretKey = process.env.JWT_SECRET_KEY || "default_secret_key";
+    const jwtSecretKey = process.env.JWT_SECRET_KEY;
     
     const decoded = jwt.verify(token, jwtSecretKey);
     req.user = decoded;

app/server.js

@@ -16,7 +16,7 @@ const authenticateToken = (req, res, next) => {
   }
 
   try {
-    const jwtSecretKey = process.env.JWT_SECRET_KEY || "defaultSecretKey";
+    const jwtSecretKey = process.env.JWT_SECRET_KEY;
     const verified = jwt.verify(token, jwtSecretKey);
     req.user = verified; 
   } catch (err) {