feat: Complete implementation of Tasks 1-5 - CIM Document Processor

Backend Infrastructure:
- Complete Express server setup with security middleware (helmet, CORS, rate limiting)
- Comprehensive error handling and logging with Winston
- Authentication system with JWT tokens and session management
- Database models and migrations for Users, Documents, Feedback, and Processing Jobs
- API routes structure for authentication and document management
- Integration tests for all server components (86 tests passing)

Frontend Infrastructure:
- React application with TypeScript and Vite
- Authentication UI with login form, protected routes, and logout functionality
- Authentication context with proper async state management
- Component tests with proper async handling (25 tests passing)
- Tailwind CSS styling and responsive design

Key Features:
- User registration, login, and authentication
- Protected routes with role-based access control
- Comprehensive error handling and user feedback
- Database schema with proper relationships
- Security middleware and validation
- Production-ready build configuration

Test Coverage: 111/111 tests passing
Tasks Completed: 1-5 (Project setup, Database, Auth system, Frontend UI, Backend infrastructure)

Ready for Task 6: File upload backend infrastructure

frontend/src/components/__tests__/ProtectedRoute.test.tsx

@@ -0,0 +1,132 @@
+import React from 'react';
+import { render, screen } from '@testing-library/react';
+import { MemoryRouter, Routes, Route } from 'react-router-dom';
+import { vi, describe, it, expect, beforeEach } from 'vitest';
+import ProtectedRoute from '../ProtectedRoute';
+
+// Mock the useAuth hook to control its output in tests
+const mockUseAuth = vi.fn();
+vi.mock('../../contexts/AuthContext', () => ({
+  useAuth: () => mockUseAuth(),
+}));
+
+const TestComponent: React.FC = () => <div>Protected Content</div>;
+const LoginComponent: React.FC = () => <div>Login Page</div>;
+const UnauthorizedComponent: React.FC = () => <div>Unauthorized Page</div>;
+
+const renderWithRouter = (ui: React.ReactNode, { initialEntries = ['/protected'] } = {}) => {
+  return render(
+    <MemoryRouter initialEntries={initialEntries}>
+      <Routes>
+        <Route path="/login" element={<LoginComponent />} />
+        <Route path="/unauthorized" element={<UnauthorizedComponent />} />
+        <Route path="/protected" element={ui} />
+      </Routes>
+    </MemoryRouter>
+  );
+};
+
+describe('ProtectedRoute', () => {
+  beforeEach(() => {
+    vi.resetAllMocks();
+  });
+
+  it('shows a loading spinner while authentication is in progress', () => {
+    mockUseAuth.mockReturnValue({
+      user: null,
+      isLoading: true,
+      isInitialized: false,
+    });
+
+    renderWithRouter(
+      <ProtectedRoute>
+        <TestComponent />
+      </ProtectedRoute>
+    );
+
+    expect(document.querySelector('.animate-spin')).toBeInTheDocument();
+    expect(screen.queryByText('Protected Content')).not.toBeInTheDocument();
+  });
+
+  it('redirects to the login page if the user is not authenticated', () => {
+    mockUseAuth.mockReturnValue({
+      user: null,
+      isLoading: false,
+      isInitialized: true,
+    });
+
+    renderWithRouter(
+      <ProtectedRoute>
+        <TestComponent />
+      </ProtectedRoute>
+    );
+
+    expect(screen.getByText('Login Page')).toBeInTheDocument();
+    expect(screen.queryByText('Protected Content')).not.toBeInTheDocument();
+  });
+
+  it('renders the protected content if the user is authenticated', () => {
+    mockUseAuth.mockReturnValue({
+      user: { id: '1', role: 'user' },
+      isLoading: false,
+      isInitialized: true,
+    });
+
+    renderWithRouter(
+      <ProtectedRoute>
+        <TestComponent />
+      </ProtectedRoute>
+    );
+
+    expect(screen.getByText('Protected Content')).toBeInTheDocument();
+  });
+
+  it('redirects to an unauthorized page if the user does not have the required role', () => {
+    mockUseAuth.mockReturnValue({
+      user: { id: '1', role: 'user' },
+      isLoading: false,
+      isInitialized: true,
+    });
+
+    renderWithRouter(
+      <ProtectedRoute requiredRole="admin">
+        <TestComponent />
+      </ProtectedRoute>
+    );
+
+    expect(screen.getByText('Unauthorized Page')).toBeInTheDocument();
+    expect(screen.queryByText('Protected Content')).not.toBeInTheDocument();
+  });
+
+  it('renders the protected content if the user has the required admin role', () => {
+    mockUseAuth.mockReturnValue({
+      user: { id: '1', role: 'admin' },
+      isLoading: false,
+      isInitialized: true,
+    });
+
+    renderWithRouter(
+      <ProtectedRoute requiredRole="admin">
+        <TestComponent />
+      </ProtectedRoute>
+    );
+
+    expect(screen.getByText('Protected Content')).toBeInTheDocument();
+  });
+
+  it('renders the protected content if the user has the required user role', () => {
+    mockUseAuth.mockReturnValue({
+      user: { id: '1', role: 'user' },
+      isLoading: false,
+      isInitialized: true,
+    });
+
+    renderWithRouter(
+      <ProtectedRoute requiredRole="user">
+        <TestComponent />
+      </ProtectedRoute>
+    );
+
+    expect(screen.getByText('Protected Content')).toBeInTheDocument();
+  });
+});