feat(tests): add Validated Tests as dedicated page, remove duplicate sidebar entry

- New /tests/validated page with its own route and sidebar link, showing
  only validated tests with Attack and Detection result badges.
- Removed the duplicate "My Pending Tasks" sidebar entry (same as All Tests).
- All Tests table no longer shows validated tests; clicking the Validated
  counter card navigates to the new page instead.
- Validated option removed from the state filter dropdown in All Tests.

frontend/src/App.tsx

@@ -18,6 +18,7 @@ const TestsPage = React.lazy(() => import("./pages/TestsPage"));
 const TestCreatePage = React.lazy(() => import("./pages/TestCreatePage"));
 const TestDetailPage = React.lazy(() => import("./pages/TestDetailPage"));
 const TestCatalogPage = React.lazy(() => import("./pages/TestCatalogPage"));
+const ValidatedTestsPage = React.lazy(() => import("./pages/ValidatedTestsPage"));
 const ReportsPage = React.lazy(() => import("./pages/ReportsPage"));
 const SystemPage = React.lazy(() => import("./pages/SystemPage"));
 const UsersPage = React.lazy(() => import("./pages/UsersPage"));
@@ -65,6 +66,7 @@ export default function App() {
         {/* ── Tests ────────────────────────────────────────────── */}
         <Route path="/tests" element={<Suspense fallback={<LoadingSpinner text="Loading…" />}><TestsPage /></Suspense>} />
         <Route path="/tests/new" element={<Suspense fallback={<LoadingSpinner text="Loading…" />}><TestCreatePage /></Suspense>} />
+        <Route path="/tests/validated" element={<Suspense fallback={<LoadingSpinner text="Loading…" />}><ValidatedTestsPage /></Suspense>} />
         <Route path="/tests/:testId" element={<Suspense fallback={<LoadingSpinner text="Loading…" />}><TestDetailPage /></Suspense>} />
         <Route path="/test-catalog" element={<Suspense fallback={<LoadingSpinner text="Loading…" />}><TestCatalogPage /></Suspense>} />
         <Route path="/test-catalog/:templateId/use" element={<Suspense fallback={<LoadingSpinner text="Loading…" />}><TestCatalogPage /></Suspense>} />