chore(test-infra): install Playwright + axe-core; configure CT and e2e runners; enable Git LFS for screenshots

B1 of TEST-INFRA-001 (RFC-WS-FRONTEND-PRIMEVUE Amendment A-1).

- Add @playwright/test, @playwright/experimental-ct-vue,
  @axe-core/playwright as dev deps in apps/app
- Add @vue/compiler-dom (transitively required by ct-vue's Vite build
  pipeline; not auto-resolved on Vite 7)
- Install Chromium via `playwright install chromium` (host cache only,
  not committed)
- Configure Git LFS clean/smudge filters globally; track
  apps/app/tests/playwright-{ct,e2e}/__screenshots__/**/*.png
- Integrate `git lfs pre-push` into lefthook.yml since LFS's per-repo
  hook would conflict with the existing sync-staleness hook
- Add playwright/index.html + playwright/index.ts hook file with the
  full provider stack (Vuetify [TEMPORARY: replaced in F3 by PrimeVue],
  Pinia, TanStack Vue Query, memory-history Router with no auth
  guards)
- Add playwright.config.ts (e2e, Chromium-only, baseURL :5173, auto-
  starts `pnpm dev` via webServer)
- Add playwright-ct.config.ts (component testing, Linux-Chromium-only
  baselines, maxDiffPixelRatio 0.001, snapshot path template,
  ssr.noExternal: ['vuetify'] mirroring vitest.config.ts)
- Add scripts: test:component, test:e2e, test:visual,
  test:visual:update
- Add smoke test proving Chromium boots in the CT runner
- Update .gitignore for Playwright runtime artifacts (test-results/,
  playwright-report/, blob-report/, playwright/.cache/)

Vitest's existing 402 tests still pass unchanged.
DoD-17 / DoD-19 CI integration deferred to TEST-INFRA-002 per Amendment
A-1 scope cut (no CI exists in this repo today).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/app/playwright.config.ts

@@ -0,0 +1,41 @@
+import { defineConfig, devices } from '@playwright/test'
+
+// E2E config — drives a real Vite dev server + a real Laravel test
+// server. Used by `pnpm test:e2e`. Component tests live in
+// playwright-ct.config.ts (different runner).
+
+export default defineConfig({
+  testDir: './tests/playwright-e2e',
+  fullyParallel: false,
+  forbidOnly: !!process.env.CI,
+  retries: 0,
+  workers: 1,
+  reporter: process.env.CI ? 'github' : 'list',
+
+  use: {
+    baseURL: process.env.E2E_FRONTEND_URL ?? 'http://localhost:5173',
+    trace: 'off',
+    video: 'off',
+    screenshot: 'off',
+    viewport: { width: 1440, height: 900 },
+  },
+
+  projects: [
+    {
+      name: 'chromium',
+      use: { ...devices['Desktop Chrome'] },
+    },
+  ],
+
+  // Auto-start the SPA dev server. Laravel's test server is started
+  // by the per-test fixture in tests/playwright-e2e/fixtures/laravel.ts
+  // because its lifecycle requires per-run seed control.
+  webServer: {
+    command: 'pnpm dev',
+    url: process.env.E2E_FRONTEND_URL ?? 'http://localhost:5173',
+    reuseExistingServer: !process.env.CI,
+    timeout: 120_000,
+    stdout: 'ignore',
+    stderr: 'pipe',
+  },
+})