update login and register page

Added Remenber Me check box, Added email Added email validation to ensure that the user enters a valid email address.
Added password strength check to require passwords to contain at least 8 characters, one uppercase letter, and one number.
Added password confirmation to ensure that the password entered by the user is the same twice.

Author: JieShi1678

code/frontend/package-lock.json

@@ -20,7 +20,8 @@
     "axios": "^1.9.0",
     "react": "^19.1.0",
     "react-dom": "^19.1.0",
-    "react-router-dom": "^6.30.0"
+    "react-router-dom": "^6.30.0",
+    "validator": "^13.15.0"
   },
   "devDependencies": {
     "@testing-library/jest-dom": "^6.6.3",

code/frontend/package.json

@@ -14,6 +14,7 @@ import {
 const Login = () => {
   const [username, setUsername] = useState('');
   const [password, setPassword] = useState('');
+  const [rememberMe, setRememberMe] = useState(false);
   const [error, setError] = useState('');
   const [loading, setLoading] = useState(false);
   const navigate = useNavigate();
@@ -26,7 +27,7 @@ const Login = () => {
     setLoading(true);
 
     try {
-      const { success, error: loginError } = await login(username, password);
+      const { success, error: loginError } = await login(username, password, rememberMe);
       if (success) {
         const from = location.state?.from?.pathname || '/home';
         navigate(from, { replace: true });
@@ -79,6 +80,16 @@ const Login = () => {
               onChange={(e) => setPassword(e.target.value)}
               disabled={loading}
             />
+            <Box sx={{ display: 'flex', alignItems: 'center', mt: 1 }}>
+              <input
+                type="checkbox"
+                id="rememberMe"
+                checked={rememberMe}
+                onChange={(e) => setRememberMe(e.target.checked)}
+                disabled={loading}
+              />
+              <label htmlFor="rememberMe" style={{ marginLeft: '8px' }}>Remember me</label>
+            </Box>
             <Button
               type="submit"
               fullWidth

code/frontend/src/pages/Login.jsx

@@ -1,6 +1,7 @@
 import { useState } from 'react';
 import { useNavigate } from 'react-router-dom';
 import { useAuth } from '../contexts/AuthContext';
+import validator from 'validator';
 import { 
   Container, 
   Paper, 
@@ -26,6 +27,18 @@ const Register = () => {
     setError('');
     setLoading(true);
 
+    if (!validator.isEmail(email)) {
+      setError('Invalid email address');
+      setLoading(false);
+      return;
+    }
+
+    if (password.length < 8 || !/[A-Z]/.test(password) || !/[0-9]/.test(password)) {
+      setError('Password must be at least 8 characters long, contain an uppercase letter, and a number');
+      setLoading(false);
+      return;
+    }
+
     if (password !== confirmPassword) {
       setError('Passwords do not match');
       setLoading(false);