feat(phase-4): implement modern Chakra UI frontend with comprehensive tracking interface

🎨 Modern React Frontend:
- Complete Chakra UI integration with custom theme and dark/light mode
- Responsive design with mobile-first navigation and layout
- Beautiful component library with cards, forms, and data visualization
- Professional typography and color system with brand consistency

🚀 Advanced URL Tracking Interface:
- Comprehensive tracking form with real-time validation using React Hook Form + Zod
- Advanced options panel with configurable parameters (max hops, timeout, headers)
- SSL, SEO, and security analysis toggles with user-friendly controls
- Smart URL normalization and method selection interface

📊 Rich Results Visualization:
- Interactive tracking results with hop-by-hop analysis tables
- Performance metrics with latency visualization and progress bars
- Status badges with color-coded redirect types and HTTP status codes
- Comprehensive error handling and user feedback system

🧭 Navigation & Layout:
- Responsive navigation bar with user authentication state
- Mobile-friendly drawer navigation with touch-optimized interactions
- Professional footer with feature highlights and API documentation links
- Breadcrumb navigation and page structure for optimal UX

🔐 Authentication Integration:
- Complete authentication context with JWT token management
- User registration and login flow preparation (backend ready)
- Protected routes and role-based access control framework
- Session management with automatic token refresh and error handling

🌟 User Experience Features:
- Toast notifications for all user actions and API responses
- Loading states and skeleton screens for smooth interactions
- Copy-to-clipboard functionality for tracking IDs and results
- Tooltips and help text for advanced features and configuration

📱 Responsive Design:
- Mobile-first design approach with breakpoint-aware components
- Touch-friendly interfaces with appropriate sizing and spacing
- Optimized layouts for desktop, tablet, and mobile viewports
- Accessible design with proper ARIA labels and keyboard navigation

🔧 Developer Experience:
- TypeScript throughout with comprehensive type safety
- React Query for efficient API state management and caching
- Custom hooks for authentication and API interactions
- Modular component architecture with clear separation of concerns

🎯 API Integration:
- Complete integration with all v2 API endpoints
- Real-time health monitoring and status display
- Backward compatibility with legacy API endpoints
- Comprehensive error handling with user-friendly messages

Ready for enhanced dashboard and analysis features in future phases!

apps/web/src/contexts/AuthContext.tsx

@@ -0,0 +1,152 @@
+/**
+ * Authentication Context for Redirect Intelligence v2
+ * 
+ * Manages user authentication state and API interactions
+ */
+
+import React, { createContext, useContext, useEffect, useState, ReactNode } from 'react';
+import { useToast } from '@chakra-ui/react';
+import { authApi, AuthUser, LoginRequest, RegisterRequest } from '../services/api';
+
+interface AuthContextType {
+  user: AuthUser | null;
+  isLoading: boolean;
+  isAuthenticated: boolean;
+  login: (credentials: LoginRequest) => Promise<void>;
+  register: (userData: RegisterRequest) => Promise<void>;
+  logout: () => void;
+  refreshUser: () => Promise<void>;
+}
+
+const AuthContext = createContext<AuthContextType | undefined>(undefined);
+
+interface AuthProviderProps {
+  children: ReactNode;
+}
+
+export function AuthProvider({ children }: AuthProviderProps) {
+  const [user, setUser] = useState<AuthUser | null>(null);
+  const [isLoading, setIsLoading] = useState(true);
+  const toast = useToast();
+
+  const isAuthenticated = !!user;
+
+  // Check for existing session on mount
+  useEffect(() => {
+    checkExistingSession();
+  }, []);
+
+  const checkExistingSession = async () => {
+    try {
+      const userData = await authApi.getCurrentUser();
+      setUser(userData);
+    } catch (error) {
+      // No existing session or session expired
+      console.log('No existing session');
+    } finally {
+      setIsLoading(false);
+    }
+  };
+
+  const login = async (credentials: LoginRequest) => {
+    try {
+      setIsLoading(true);
+      const response = await authApi.login(credentials);
+      setUser(response.user);
+      
+      toast({
+        title: 'Login successful',
+        description: `Welcome back, ${response.user.name}!`,
+        status: 'success',
+        duration: 3000,
+        isClosable: true,
+      });
+    } catch (error: any) {
+      const message = error.response?.data?.message || 'Login failed';
+      toast({
+        title: 'Login failed',
+        description: message,
+        status: 'error',
+        duration: 5000,
+        isClosable: true,
+      });
+      throw error;
+    } finally {
+      setIsLoading(false);
+    }
+  };
+
+  const register = async (userData: RegisterRequest) => {
+    try {
+      setIsLoading(true);
+      const response = await authApi.register(userData);
+      
+      toast({
+        title: 'Registration successful',
+        description: `Welcome, ${response.user.name}! Please log in to continue.`,
+        status: 'success',
+        duration: 5000,
+        isClosable: true,
+      });
+    } catch (error: any) {
+      const message = error.response?.data?.message || 'Registration failed';
+      toast({
+        title: 'Registration failed',
+        description: message,
+        status: 'error',
+        duration: 5000,
+        isClosable: true,
+      });
+      throw error;
+    } finally {
+      setIsLoading(false);
+    }
+  };
+
+  const logout = () => {
+    authApi.logout();
+    setUser(null);
+    
+    toast({
+      title: 'Logged out',
+      description: 'You have been successfully logged out.',
+      status: 'info',
+      duration: 3000,
+      isClosable: true,
+    });
+  };
+
+  const refreshUser = async () => {
+    try {
+      const userData = await authApi.getCurrentUser();
+      setUser(userData);
+    } catch (error) {
+      // Session expired or invalid
+      setUser(null);
+    }
+  };
+
+  const value: AuthContextType = {
+    user,
+    isLoading,
+    isAuthenticated,
+    login,
+    register,
+    logout,
+    refreshUser,
+  };
+
+  return (
+    <AuthContext.Provider value={value}>
+      {children}
+    </AuthContext.Provider>
+  );
+}
+
+export function useAuth() {
+  const context = useContext(AuthContext);
+  if (context === undefined) {
+    throw new Error('useAuth must be used within an AuthProvider');
+  }
+  return context;
+}