Use Playwright container image for CI e2e job

[Copilot]

Playwright setup in CI was spending significant time installing browsers and system dependencies at runtime. This PR switches the e2e workflow to the prebuilt Playwright container model used in Mosaic to reduce setup overhead.

• CI workflow: run e2e in Playwright container

  • Updated the e2e job in .github/workflows/test.yml to run in:
    • mcr.microsoft.com/playwright:v1.56.1-noble
  • Set container runtime user to match the Mosaic pattern:
    • options: --user 1001

• Removed redundant Playwright bootstrap

  • Dropped the explicit install step:
    • npx playwright install --with-deps chromium
  • Kept the existing test command unchanged:
    • npx playwright test --project=chromium --reporter=github,html

e2e:
  runs-on: ubuntu-latest
  container:
    image: mcr.microsoft.com/playwright:v1.56.1-noble
    options: --user 1001
  steps:
    - uses: actions/checkout@v6
    - uses: actions/setup-node@v6
      with:
        cache: 'npm'
        node-version: 24
    - run: npm ci
    - run: npx playwright test --project=chromium --reporter=github,html

[domoritz]

@copilot check the logs of the failing test

[Copilot]

@copilot check the logs of the failing test

Checked the failing E2E logs: Playwright reported a container/runtime mismatch (current: mcr.microsoft.com/playwright:v1.60.0-noble, required: mcr.microsoft.com/playwright:v1.56.1-noble) and missing browser executable. I fixed this by updating the workflow container tag to v1.56.1-noble in commit ff556a8.