Add GitHub Actions Playwright integration workflow for JA/EN website locale rendering with screenshot artifacts

[Copilot]

This PR adds CI coverage for website localization by verifying that both Japanese and English pages render correctly in GitHub Actions. A new dedicated workflow (website_integration_test.yaml) builds the Docusaurus site, serves it, runs Playwright assertions against locale-specific routes, and uploads locale page screenshots as workflow artifacts.

• Workflow: website locale integration test

  • Added .github/workflows/website_integration_test.yaml
  • Triggers on:
    • pull_request changes under website/** and the workflow file
    • push to main for the same paths
    • manual dispatch

• Website runtime setup in CI

  • Reuses existing Node version resolution (nodenv/actions/node-version + actions/setup-node)
  • Runs website dependency install and static build in website/
  • Starts yarn serve on 127.0.0.1:3000
  • Waits for both locale endpoints to become reachable before testing

• Playwright assertions for JA/EN correctness

  • Executes Playwright checks against:
    • /pedax/ (default locale: JA)
    • /pedax/en/ (EN locale)
  • Validates page load success and locale-specific visible text
  • Captures full-page screenshots during tests:
    • ja-page.png
    • en-page.png

• Artifacts

  • Uploads screenshots using actions/upload-artifact@v4
  • Artifact name: website-integration-screenshots
  • Upload step runs with if: always() so screenshots are preserved for debugging

- name: Verify JA/EN website pages with Playwright
  run: |
    yarn serve --port 3000 --host 127.0.0.1 >"$RUNNER_TEMP/docusaurus-serve.log" 2>&1 &
    # wait until /pedax/ and /pedax/en/ are reachable...
    npm install --no-fund --no-audit @playwright/test
    npx playwright install chromium
    SCREENSHOT_DIR="$RUNNER_TEMP/playwright/screenshots" npx playwright test website.integration.spec.js --reporter=line

- name: Upload website locale screenshots
  if: always()
  uses: actions/upload-artifact@v4
  with:
    name: website-integration-screenshots
    path: ${{ runner.temp }}/playwright/screenshots

[sensuikan1973]

@copilot website integration test について、テスト中に確認した en と ja のページのスクショをその wrokflow の artifacts に入れて欲しい

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.13%. Comparing base (d408d59) to head (800715d).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2925   +/-   ##
=======================================
  Coverage   94.13%   94.13%           
=======================================
  Files          52       52           
  Lines        1483     1483           
=======================================
  Hits         1396     1396           
  Misses         87       87           

Flag	Coverage Δ
integration_test	65.00% <ø> (ø)
macos-latest	93.05% <ø> (ø)
ubuntu	93.59% <ø> (ø)
widget_test	90.28% <ø> (ø)
windows	93.45% <ø> (ø)

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[Copilot]

@copilot website integration test について、テスト中に確認した en と ja のページのスクショをその wrokflow の artifacts に入れて欲しい

対応しました。800715d で Playwright テスト内で ja-page.png / en-page.png を保存し、workflow artifact website-integration-screenshots としてアップロードするように変更しています。