Migrate PR checks from Azure Pipelines to GitHub Actions

[Copilot]

Moves PR validation from Azure Pipelines to GitHub Actions, using microsoft/react-native-test-app/.github/actions/setup-toolchain for environment setup (same pattern as rnx-kit). Adds a catch-all PR job so all checks can be retried at once (mirrors react-native-macos).

Jobs

• JS PR — checkchange, prettier, lint-lockfile, buildci, check-for-changed-files
• Android PR — bundle (E2E disabled, matching ADO)
• macOS PR — bundle → pod install → xcodebuild → Appium E2E + artifact upload
• iOS PR — bundle → pod install → xcodebuild (E2E disabled, matching ADO)
• Windows PR — bundle → WinAppDriver 1.1 → UWP build → Appium E2E + artifact upload
• Win32 PR — bundle → WinAppDriver 1.1 → Appium E2E + artifact upload
• Test Links — markdown link validation
• PR — catch-all depending on all of the above

Catch-all job

pr:
  name: PR
  runs-on: ubuntu-latest
  needs: [js, android, macos, ios, windows, win32, test-links]
  steps:
    - name: All required jobs passed
      run: echo "All required jobs completed."

Notes

• Concurrency group per PR with cancel-in-progress: true
• permissions: { contents: read } (least privilege)
• E2E artifacts uploaded with if: always() so reports/errorShots are available on failure
• Reuses existing .ado/scripts/xcodebuild.sh
• ADO pipeline left in place for removal once GHA is validated
• setup-toolchain transitively uses gradle/actions/setup-gradle and ruby/setup-ruby which need to be allowlisted in org Actions policy

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.