feat: Update login navigation and authentication flow

- Changed navigation from '/editor' to '/tests' after successful login.
- Introduced token state management in AuthContext for better handling of authentication.
- Updated login function to store JWT instead of Google token.
- Added error handling for login and test fetching processes.

style: Enhance UI with new footer and test list styles

- Added a footer component with copyright information.
- Created a new TestList component with improved styling and animations.
- Implemented responsive design for test cards and filter tabs.
- Added loading and error states for better user experience.

fix: Improve API interaction for test fetching and password verification

- Refactored API calls to use a centralized studentApi utility.
- Enhanced error handling for API responses, including unauthorized access.
- Implemented password verification for protected tests before starting them.

Frontend/src/components/Login.jsx

@@ -14,7 +14,7 @@ const Login = () => {
   useEffect(() => {
     const token = localStorage.getItem('monaco_token');
     if (token) {
-      navigate('/editor');
+      navigate('/tests');
     }
   }, [navigate]);
 
@@ -39,7 +39,7 @@ const Login = () => {
         const success = await login(userInfo.email, credentialResponse.credential, userInfo);
         
         if (success) {
-          navigate('/editor');
+          navigate('/tests');
         } else {
           throw new Error('Authentication failed');
         }