Add test-coverage-detector workflow (detector/fixer pair for test-improver)

[Copilot]

Adds a scheduled Test Coverage Detector workflow that reports high-confidence coverage gaps and serves as the detector counterpart to test-improver.

Detector workflow

• Runs coverage tools when available; falls back to code analysis when coverage tooling is unavailable.
• Reviews 28-day git history to find recent code changes without corresponding test updates.
• Uses Pick Three, Keep One parallel investigation with sub-agents during gap discovery.
• Applies a high bar for reporting and defaults to noop unless gaps are concrete, user-scenario-backed, and actionable.
• Safe output: create-issue (max 1, expires in 7d).

New files

• .github/workflows/gh-aw-test-coverage-detector.md — workflow source (scheduled-audit based)
• .github/workflows/gh-aw-test-coverage-detector.lock.yml — compiled workflow lock file
• gh-agent-workflows/test-coverage-detector/ — workflow README + trigger example
• docs/workflows/gh-agent-workflows/test-coverage.md — detector/fixer pair documentation
• .github/workflows/trigger-test-coverage-detector.yml — dogfood trigger workflow

Updated references

• Added Test Coverage to the detector/fixer pair docs and MkDocs navigation.
• Added test-coverage-detector to workflow catalogs (gh-agent-workflows/README.md) and setup tooling (scripts/quick-setup.sh).
• Added detector triggering in CI helper scripts and smoke-test install matrix.
• Added pairing cross-references in both workflow READMEs.

Quick install

# Detector only
mkdir -p .github/workflows && curl -sL \
  https://raw.githubusercontent.com/elastic/ai-github-actions/v0/gh-agent-workflows/test-coverage-detector/example.yml \
  -o .github/workflows/test-coverage-detector.yml

# Full loop (detector + fixer)
mkdir -p .github/workflows && \
curl -sL https://raw.githubusercontent.com/elastic/ai-github-actions/v0/gh-agent-workflows/test-coverage-detector/example.yml \
  -o .github/workflows/test-coverage-detector.yml && \
curl -sL https://raw.githubusercontent.com/elastic/ai-github-actions/v0/gh-agent-workflows/test-improver/example.yml \
  -o .github/workflows/test-improver.yml

• Fixes Create detector version of test-improver #483

Generated by Update PR Body for issue #488

[coderabbitai]

Caution

Review failed

The pull request is closed.

ℹ️ Recent review info

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 340573f and fbc6c72.

📒 Files selected for processing (2)

• docs/workflows/gh-agent-workflows.md
• scripts/quick-setup.sh

---

📝 Walkthrough

Walkthrough

This pull request adds a new Test Coverage Detector workflow (generated lockfile and human-readable workflow), a reusable trigger workflow, example and trigger files, and supporting documentation and README entries. It integrates the detector into installation and CI scripts (quick-setup, smoke-test-install, trigger scripts), updates navigation (mkdocs.yml), and includes docs and examples for pairing the detector with the Test Improver. The detector workflow is a multi-job Copilot-driven automation producing artifacts (prompts, agent outputs, safe-outputs, threat-detection logs) and implements activation, agent execution, safe outputs, threat detection, conclusion, and cleanup flows.

Possibly related PRs

• elastic/ai-github-actions PR 312: Adds workflow/fragments and tooling changes that align with introducing the Test Coverage Detector workflow and related fragments.
• elastic/ai-github-actions PR 173: Modifies quick-setup and related installer wiring that this change extends by adding the test-coverage-detector to defaults.
• elastic/ai-github-actions PR 335: Adjusts generated workflow generation and docs for lock/trigger files, which overlap with this PR’s added generated lock and trigger workflows.

🚥 Pre-merge checks | ✅ 2

✅ Passed checks (2 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	The PR successfully implements the detector version of test-improver (#483), including workflow definitions, documentation, and integration into existing tooling.
Out of Scope Changes check	✅ Passed	All changes directly support the test-coverage-detector feature. Updates to documentation, scripts, and workflows are aligned with adding and integrating the new detector.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

• 📝 Generate docstrings (stacked PR)
• 📝 Generate docstrings (commit on current branch)

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch copilot/create-detector-version-test-improver

---

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[github-actions]

[LOW] Broken docs link for Test Coverage detector/fixer pair

This row links to gh-agent-workflows/test-coverage-detector.md, but that page does not exist in this PR (mkdocs.yml and docs add workflows/gh-agent-workflows/test-coverage.md). The current link will 404 in rendered docs.

Suggested change

	| [Test Coverage Detector](gh-agent-workflows/test-coverage-detector.md) | [Test Improver](gh-agent-workflows/test-improver.md) | Test coverage gaps |
	| [Test Coverage Detector](gh-agent-workflows/test-coverage.md) | [Test Improver](gh-agent-workflows/test-improver.md) | Test coverage gaps |

[strawgate]

/ai please fix the broken link