[AZ-456] Test infrastructure: Vitest + MSW + Playwright + scripts

Scaffolds the Blackbox test project per AZ-456 / environment.md across
the three profiles:

- fast  : Vitest 3.x + jsdom + MSW 2.x + RTL/jest-dom; tests/setup.ts
          boots the MSW Node server with onUnhandledRequest:'error',
          afterEach resets handlers, clears bearer + navigate-to-login
          spy. Default handlers ship for every suite service plus OWM
          and tile stand-ins. Fixtures mirror seed_* in test-data.md.
- e2e   : Playwright ^1.49 with chromium + firefox projects against the
          suite docker-compose stack; owm-stub + tile-stub Bun servers,
          playwright-runner image, seeds.sql for the test-db.
- static: scripts/run-tests.sh extended — tsc --noEmit (test config),
          vite build, ripgrep checks (with grep -r fallback), CSV
          report at test-output/static-report.csv per AC-7 columns.

Smoke tests cover AC-3, AC-4 (fast, 5 tests, PASS) and AC-1, AC-2,
AC-5, AC-8 (e2e, gated by Risk 4 docker availability). Static profile
(13 checks) PASS — STC-SEC1 (no literal OWM key) lifted from
QUARANTINE per AZ-447 with a narrowed pattern.

Files:
  +24 tests/**, +10 e2e/**, +vitest.config.ts, +tsconfig.test.json
  ~package.json (test scripts + devDeps for vitest, @testing-library/*,
   msw, @playwright/test, jsdom, @types/node, @vitest/coverage-v8)
  ~scripts/run-tests.sh, scripts/run-performance-tests.sh — switched
   RESULTS_DIR to test-output/, compose path to project-local
  ~.gitignore — added /test-output/

Verification:
  bun run test:fast        → 11 / 11 PASS
  ./scripts/run-tests.sh   → static 13/13 + fast 11/11 PASS, exit 0

Tracker: AZ-456 → In Testing.
Co-authored-by: Cursor <cursoragent@cursor.com>

tests/helpers/render.tsx

@@ -0,0 +1,39 @@
+import type { ReactElement, ReactNode } from 'react'
+import { render, type RenderOptions, type RenderResult } from '@testing-library/react'
+import { MemoryRouter } from 'react-router-dom'
+import { I18nextProvider } from 'react-i18next'
+import i18n from '../../src/i18n/i18n'
+import { AuthProvider } from '../../src/auth/AuthContext'
+
+export interface RenderWithProvidersOptions extends RenderOptions {
+  /** Initial route(s) for the in-memory router. Defaults to ['/']. */
+  initialEntries?: string[]
+  /** Initial entry index. Defaults to 0. */
+  initialIndex?: number
+  /** Skip wrapping in <AuthProvider>. Useful for tests that mock auth themselves. */
+  withoutAuth?: boolean
+  /** Skip wrapping in <I18nextProvider>. */
+  withoutI18n?: boolean
+}
+
+export function renderWithProviders(
+  ui: ReactElement,
+  {
+    initialEntries = ['/'],
+    initialIndex = 0,
+    withoutAuth,
+    withoutI18n,
+    ...rtl
+  }: RenderWithProvidersOptions = {},
+): RenderResult {
+  const Wrapper = ({ children }: { children: ReactNode }) => {
+    let tree = <MemoryRouter initialEntries={initialEntries} initialIndex={initialIndex}>{children}</MemoryRouter>
+    if (!withoutAuth) tree = <AuthProvider>{tree}</AuthProvider>
+    if (!withoutI18n) tree = <I18nextProvider i18n={i18n}>{tree}</I18nextProvider>
+    return tree
+  }
+  return render(ui, { wrapper: Wrapper, ...rtl })
+}
+
+export { screen, within, fireEvent, waitFor, act } from '@testing-library/react'
+export { default as userEvent } from '@testing-library/user-event'