Add PR integration test skill

[Kai Tao (vanzue)]

Summary

• add a pr-integration-test project skill for designing integration/E2E coverage for a target PR or regression
• require behavior-contract analysis, cross-component boundary proof, positive/negative/replay coverage, and related regression execution
• guide exact-title release-checklist mapping, stable checklist ID assignment, and full/incremental report verification
• document deterministic oracle selection, prerequisite gating, branch strategy, stale-build prevention, and test-PR delivery

Validation

• verified required skill frontmatter, name/description constraints, and SKILL.md size
• verified all bundled relative links resolve
• reviewed the workflow for substantive correctness and incorporated feedback for -UpdateReport, release exclusions, portable repository search, and architecture-specific WTA targets
• git diff --check passes

[Copilot]

Pull request overview

Adds a new repository Agent Skill (pr-integration-test) to standardize how contributors design and validate integration/E2E coverage for a target PR or regression, including release-checklist mapping and report verification using the existing ItE2E tooling.

Changes:

• Introduces .github/skills/pr-integration-test/SKILL.md with the skill’s entrypoint guidance, quality gates, and references.
• Adds a detailed, phase-based workflow in .github/skills/pr-integration-test/references/workflow.md covering PR analysis, test design, checklist wiring, validation, and delivery.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
.github/skills/pr-integration-test/SKILL.md	Adds the new skill’s frontmatter plus high-level standards and gating criteria for PR→integration-test work.
.github/skills/pr-integration-test/references/workflow.md	Provides the detailed step-by-step procedure, including checklist/report validation and stale-build prevention guidance.

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (2)

.github/skills/pr-integration-test/references/workflow.md:186

• This PowerShell example includes an unquoted Feature.<Name>.Tests.ps1 placeholder. In PowerShell, <...> in an unquoted argument is a parse error; quote the path so the command is syntactically valid when copied.

  -Path test/e2e/tests/Feature.<Name>.Tests.ps1 `

.github/skills/pr-integration-test/references/workflow.md:205

• These PowerShell placeholders (<existing-release-report.md>, etc.) are unquoted, which triggers a PowerShell parse error due to <...>. Quote the placeholder values so the example is syntactically valid when copied.

  -Report <existing-release-report.md> `
  -ResultsXml <results.xml> `
  -OutFile <updated-release-report.md>

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (1)

.github/skills/pr-integration-test/references/workflow.md:62

• The example $pattern = 'feature|event|setting|command' will be interpreted by git grep -E as regex alternation, which makes it look like a placeholder but actually drives a very broad search if copy/pasted verbatim. Using an explicit placeholder token makes it clear the reader should substitute the PR-specific keyword(s).

$pattern = 'feature|event|setting|command'
git grep -n -E $pattern -- test/e2e tools/wta/src src/cascadia