Add reusable Playwright test harness

[gaelcolas]

Summary

Add a reusable Playwright end-to-end test harness to this task module so Sampler-based repositories can run browser tests through the same build entry point and reporting conventions as their Pester tests.

Scope

• Add a shipped InvokeBuild task file under source/Tasks and export it through a Task.* alias and AliasesToExport metadata.
• Keep reusable helper logic in one-function-per-file module functions under source/Public or source/Private; do not add a sibling task PSM1.
• Provide Pester 5 wrapper tasks for importing Pester, running Playwright wrappers, failing the build on test failures, and a convenient testUI workflow alias.
• Support defaults-first configuration where invocation parameters override build.yaml, and build.yaml overrides module defaults.
• Default test discovery to tests/playwright, with configurable run paths, tags, and excluded tags.
• Write Pester NUnit XML results under output/playwright.
• Document a Node Playwright harness using package.json, playwright.config.ts, and browser test folders such as tests/smoke.
• Configure Playwright to retain traces, screenshots, and videos on failures and emit a JUnit result file under output/playwright.
• Define how npm ci and the required Playwright browser installation are bootstrapped locally and in CI.
• Keep secrets and target URLs environment-driven; no credentials should be committed.
• Add unit tests for configuration conversion, path resolution, filtering, and failure propagation.
• Add WikiSource documentation for consumer setup, configuration, task reference, output files, and CI integration.

Suggested task surface

• Import_Pester_For_Playwright
• Invoke_Playwright_Pester_Tests_v5
• Fail_Build_If_Playwright_Tests_Failed
• Playwright_Tests_Stop_On_Fail
• testUI

Acceptance criteria

• A consumer can add the module through RequiredModules.psd1, import its Task.* alias through ModuleBuildTasks, and run ./build.ps1 -Tasks testUI.
• Missing configured test paths fail with a clear actionable error.
• Playwright and Pester result files are generated in deterministic locations below output/playwright.
• Browser diagnostics are retained on failures and can be uploaded as CI artifacts.
• A failing browser test fails the InvokeBuild workflow.
• The harness works on supported PowerShell and GitHub-hosted runner environments.
• Public/private helper functions follow this repository's source layout and test conventions.
• Documentation describes the complete setup without depending on repository-specific application details.

[gaelcolas]

CI bootstrap and licensing considerations

The harness should include a dedicated Windows E2E job rather than adding PSU and browser setup to every unit-test matrix leg.

Suggested job bootstrap

1. Download the module build artifact produced by the normal build job.
2. Install a pinned supported PowerShell Universal version using the official Devolutions.PowerShellUniversal module and Install-PSUServer. Prefer the official installer path over relying on the Chocolatey community package.
3. Start PSU on a deterministic localhost port and wait for a health endpoint before continuing.
4. When licensed scenarios are enabled, expose the contents of a license file through a masked PSULICENSE secret and environment variable before starting PSU.
5. Bootstrap the test PSU instance, including any required administrator identity, application token, repository configuration, and deployment fixture.
6. Run npm ci in the Playwright test directory.
7. Install the required browser and operating-system dependencies, for example npx playwright install --with-deps chromium.
8. Run ./build.ps1 -Tasks testUI so Pester remains the build entry point and result aggregator.
9. Upload output/playwright, including NUnit/JUnit results, traces, screenshots, and videos, with if: always().

Licensing

PowerShell Universal documents Apps, app tokens, module management, and several automation capabilities as licensed features. An unlicensed instance is therefore unlikely to cover deployment and application UI scenarios.

A free developer license is available for non-production development and testing, but its Devolutions Account login flow is interactive and is not a good fit for ephemeral headless runners. For CI, support an optional license supplied through the PSULICENSE environment variable.

Licensed E2E jobs must run only for trusted pushes, manual runs, or internal pull requests. GitHub does not expose repository secrets to workflows triggered from forks. Public pull requests should either skip licensed tests or run a deliberately limited unlicensed smoke suite.

Do not commit a license, PSU token, administrator credential, or storage state. Document the required secret names and generate short-lived test credentials where the PSU bootstrap APIs support it.

References:

• https://docs.devolutions.net/powershell-universal/get-started
• https://docs.devolutions.net/powershell-universal/licensing