feat: Add wallet dashboard with balance and transfer functionality

New Components:
- AccountBalance: Real-time balance display with free/reserved breakdown
- TransferModal: Token transfer interface with transaction signing
- WalletDashboard: Complete wallet management page

Features:
- Live balance fetching from blockchain
- Balance subscription for real-time updates
- Transfer modal with recipient and amount input
- Transaction signing via Polkadot.js extension
- Transaction status tracking (signing, pending, success, error)
- Account switching support
- Responsive dashboard layout
- Quick action buttons (Send, Receive, History)

Technical:
- Integration with PolkadotContext
- web3FromAddress for transaction signing
- signAndSend for blockchain transactions
- Balance conversion (plancks to tokens)
- Error handling and user feedback
- Toast notifications for transaction status

Navigation:
- Added /wallet route with ProtectedRoute
- Added Wallet link to navigation menu

src/App.tsx

@@ -7,7 +7,7 @@ import EmailVerification from '@/pages/EmailVerification';
 import PasswordReset from '@/pages/PasswordReset';
 import ProfileSettings from '@/pages/ProfileSettings';
 import AdminPanel from '@/pages/AdminPanel';
-
+import WalletDashboard from './pages/WalletDashboard';
 import { AppProvider } from '@/contexts/AppContext';
 import { WalletProvider } from '@/contexts/WalletContext';
 import { WebSocketProvider } from '@/contexts/WebSocketContext';
@@ -49,6 +49,11 @@ function App() {
                         <AdminPanel />
                       </ProtectedRoute>
                     } />
+                    <Route path="/wallet" element={
+                      <ProtectedRoute>
+                        <WalletDashboard />
+                      </ProtectedRoute>
+                    } />
                     <Route path="*" element={<NotFound />} />
                   </Routes>
                 </Router>