Add initial frontend component tests

- Create login-form.test.tsx with 8 test cases (positive and negative)
- Create register-form.test.tsx with 10 test cases
- Set up test directory structure at frontend/src/components/__tests__
- Mock auth-context and next/navigation for testing

frontend/src/components/__tests__/login-form.test.tsx

@@ -0,0 +1,144 @@
+import { render, screen, fireEvent, waitFor } from '@testing-library/react';
+import { LoginForm } from '../login-form';
+import { useAuth } from '@/lib/auth-context';
+import { useRouter } from 'next/navigation';
+
+// Mock the auth context
+jest.mock('@/lib/auth-context', () => ({
+  useAuth: jest.fn(),
+}));
+
+// Mock next/navigation
+jest.mock('next/navigation', () => ({
+  useRouter: jest.fn(),
+}));
+
+describe('LoginForm', () => {
+  const mockLogin = jest.fn();
+  const mockPush = jest.fn();
+
+  beforeEach(() => {
+    jest.clearAllMocks();
+    (useAuth as jest.Mock).mockReturnValue({
+      login: mockLogin,
+      error: null,
+    });
+    (useRouter as jest.Mock).mockReturnValue({
+      push: mockPush,
+    });
+  });
+
+  // Positive Tests
+  describe('Positive Tests', () => {
+    it('renders login form with all fields', () => {
+      render(<LoginForm />);
+      
+      expect(screen.getByLabelText(/email/i)).toBeInTheDocument();
+      expect(screen.getByLabelText(/password/i)).toBeInTheDocument();
+      expect(screen.getByRole('button', { name: /login/i })).toBeInTheDocument();
+    });
+
+    it('submits form with valid credentials', async () => {
+      mockLogin.mockResolvedValueOnce(undefined);
+      
+      render(<LoginForm />);
+      
+      fireEvent.change(screen.getByLabelText(/email/i), {
+        target: { value: 'user@example.com' },
+      });
+      fireEvent.change(screen.getByLabelText(/password/i), {
+        target: { value: 'password123' },
+      });
+      
+      fireEvent.click(screen.getByRole('button', { name: /login/i }));
+      
+      await waitFor(() => {
+        expect(mockLogin).toHaveBeenCalledWith('user@example.com', 'password123');
+      });
+      
+      await waitFor(() => {
+        expect(mockPush).toHaveBeenCalledWith('/dashboard');
+      });
+    });
+
+    it('shows loading state while submitting', async () => {
+      mockLogin.mockImplementation(() => new Promise(() => {})); // Never resolves
+      
+      render(<LoginForm />);
+      
+      fireEvent.change(screen.getByLabelText(/email/i), {
+        target: { value: 'user@example.com' },
+      });
+      fireEvent.change(screen.getByLabelText(/password/i), {
+        target: { value: 'password123' },
+      });
+      
+      fireEvent.click(screen.getByRole('button', { name: /login/i }));
+      
+      expect(screen.getByText(/logging in/i)).toBeInTheDocument();
+      expect(screen.getByRole('button', { name: /logging in/i })).toBeDisabled();
+    });
+
+    it('displays error message from auth context', () => {
+      (useAuth as jest.Mock).mockReturnValue({
+        login: mockLogin,
+        error: 'Invalid credentials',
+      });
+      
+      render(<LoginForm />);
+      
+      expect(screen.getByText(/invalid credentials/i)).toBeInTheDocument();
+    });
+  });
+
+  // Negative Tests
+  describe('Negative Tests', () => {
+    it('prevents submission when email is empty', () => {
+      render(<LoginForm />);
+      
+      fireEvent.change(screen.getByLabelText(/email/i), {
+        target: { value: '' },
+      });
+      
+      const form = screen.getByRole('form');
+      expect(form).toBeInTheDocument();
+    });
+
+    it('prevents submission when password is empty', () => {
+      render(<LoginForm />);
+      
+      fireEvent.change(screen.getByLabelText(/password/i), {
+        target: { value: '' },
+      });
+      
+      const form = screen.getByRole('form');
+      expect(form).toBeInTheDocument();
+    });
+
+    it('enforces minimum password length of 8 characters', () => {
+      render(<LoginForm />);
+      
+      const passwordInput = screen.getByLabelText(/password/i);
+      expect(passwordInput).toHaveAttribute('minLength', '8');
+    });
+
+    it('handles login failure gracefully', async () => {
+      mockLogin.mockRejectedValueOnce(new Error('Login failed'));
+      
+      render(<LoginForm />);
+      
+      fireEvent.change(screen.getByLabelText(/email/i), {
+        target: { value: 'user@example.com' },
+      });
+      fireEvent.change(screen.getByLabelText(/password/i), {
+        target: { value: 'password123' },
+      });
+      
+      fireEvent.click(screen.getByRole('button', { name: /login/i }));
+      
+      await waitFor(() => {
+        expect(mockPush).not.toHaveBeenCalled();
+      });
+    });
+  });
+});