M-029 Pass 3 batch C (FINAL): T-1 tests for 5 list pages — Pass 3 complete

Closes M-029 Pass 3 fully. Every src/pages/*.tsx now has a *.test.tsx peer.

Audit recon: 'comm -23 <pages> <test-peers>' returns zero (all 14 T-1-deferred

pages now covered).

Test files added (each ships render-coverage + an XSS-hardening contract):

  - HealthMonitorPage.test.tsx     endpoint URL + last_error payloads

  - JobsPage.test.tsx              type / certificate_id / agent_id /

                                    error_message payloads

  - NetworkScanPage.test.tsx       network_range / agent_id / last_scan_message

                                    payloads

  - ProfilesPage.test.tsx          profile name / description / EKUs payloads

  - AgentFleetPage.test.tsx        agent name / hostname / OS / arch / IP

                                    payloads (mirrors the M-003 MCP fence shape)

Pass 3 totals across batches A + B + C: 14 new test files, 14/14 T-1-deferred

pages closed. Each test pins three invariants:

  1. The page renders against mock data without crashing.

  2. No live <script data-xss='...'> attaches to the DOM.

  3. The literal payload appears as escaped text content (proving the page

     surfaces the data without rendering it as HTML).

M-029 status after Pass 3:

  Pass 1 — useMutation -> useTrackedMutation     COMPLETE (6 batches, 56 -> 0)

  Pass 2 — useState pagination -> useListParams  COMPLETE (CertificatesPage)

  Pass 3 — XSS-hardening test suites             COMPLETE (14/14 pages)

M-029 IS NOW READY TO CLOSE.

web/src/pages/HealthMonitorPage.test.tsx

@@ -0,0 +1,81 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import { render, screen, waitFor, cleanup } from '@testing-library/react';
+import { QueryClient, QueryClientProvider } from '@tanstack/react-query';
+import { MemoryRouter } from 'react-router-dom';
+import type { ReactNode } from 'react';
+
+// -----------------------------------------------------------------------------
+// M-029 Pass 3 (Audit M-026): HealthMonitorPage XSS-hardening + render
+// coverage. The endpoint URL is operator-supplied; the last_check error
+// message is server-rendered probe output.
+// -----------------------------------------------------------------------------
+
+vi.mock('../api/client', () => ({
+  listHealthChecks: vi.fn(),
+  createHealthCheck: vi.fn(),
+  deleteHealthCheck: vi.fn(),
+  acknowledgeHealthCheck: vi.fn(),
+  getHealthCheckSummary: vi.fn(),
+}));
+
+import HealthMonitorPage from './HealthMonitorPage';
+import * as client from '../api/client';
+
+function renderWithQuery(ui: ReactNode) {
+  const qc = new QueryClient({
+    defaultOptions: { queries: { retry: false, gcTime: 0, staleTime: 0 } },
+  });
+  return render(
+    <QueryClientProvider client={qc}>
+      <MemoryRouter>{ui}</MemoryRouter>
+    </QueryClientProvider>,
+  );
+}
+
+const xssPayload = '<script data-xss="health">window.__xss_pwned__=1;</script>';
+
+const xssCheck = {
+  id: 'hc-xss-001',
+  endpoint: xssPayload,
+  status: 'failing',
+  last_error: xssPayload,
+  last_checked_at: new Date().toISOString(),
+  acknowledged: false,
+};
+
+describe('HealthMonitorPage — render + XSS hardening (M-026 / M-029 Pass 3)', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    cleanup();
+    delete (window as unknown as { __xss_pwned__?: number }).__xss_pwned__;
+    vi.mocked(client.getHealthCheckSummary).mockResolvedValue({ total: 0, failing: 0, ok: 0 } as never);
+  });
+
+  it('renders the page header when listHealthChecks resolves', async () => {
+    vi.mocked(client.listHealthChecks).mockResolvedValue({ data: [], total: 0, page: 1, per_page: 100 } as never);
+    renderWithQuery(<HealthMonitorPage />);
+    await waitFor(() => {
+      expect(screen.getByText(/Health/i)).toBeInTheDocument();
+    });
+  });
+
+  it('does NOT execute <script> payloads in endpoint / last_error', async () => {
+    vi.mocked(client.listHealthChecks).mockResolvedValue({
+      data: [xssCheck],
+      total: 1,
+      page: 1,
+      per_page: 100,
+    } as never);
+    renderWithQuery(<HealthMonitorPage />);
+    await waitFor(() => {
+      expect(document.body.textContent ?? '').toContain('<script data-xss="health">');
+    });
+
+    const liveScripts = document.querySelectorAll('script[data-xss="health"]');
+    expect(liveScripts.length, 'health-check fields must not inject a live <script>').toBe(0);
+    expect(
+      (window as unknown as { __xss_pwned__?: number }).__xss_pwned__,
+      'health-check <script> body must not have executed',
+    ).toBeUndefined();
+  });
+});