Create Rate Limit Admin Dashboard

Add a React admin dashboard component to visualize rate limit metrics and statistics, including data fetching from the rate-limit-metrics edge function, charts and statistics, and admin routes/integration. Includes setup for routing and UI scaffolding to display total requests, block rate, top blocked IPs/users, and recent activity with interactive charts.

src/App.tsx

@@ -74,6 +74,7 @@ const AdminEmailSettings = lazy(() => import("./pages/admin/AdminEmailSettings")
 const ErrorMonitoring = lazy(() => import("./pages/admin/ErrorMonitoring"));
 const ErrorLookup = lazy(() => import("./pages/admin/ErrorLookup"));
 const TraceViewer = lazy(() => import("./pages/admin/TraceViewer"));
+const RateLimitMetrics = lazy(() => import("./pages/admin/RateLimitMetrics"));
 
 // User routes (lazy-loaded)
 const Profile = lazy(() => import("./pages/Profile"));
@@ -396,6 +397,14 @@ function AppContent(): React.JSX.Element {
                       </AdminErrorBoundary>
                     } 
                   />
+                  <Route 
+                    path="/admin/rate-limit-metrics" 
+                    element={
+                      <AdminErrorBoundary section="Rate Limit Metrics">
+                        <RateLimitMetrics />
+                      </AdminErrorBoundary>
+                    } 
+                  />
                   
                   {/* Utility routes - lazy loaded */}
                   <Route path="/force-logout" element={<ForceLogout />} />