Documentation and CI follow-ups

Objective

Complete documentation and enhance CI pipeline for comprehensive testing.

Tasks

Documentation

• Create TESTING.md - Testing guide for contributors
• Update README.md with:
  • GitHub integration setup instructions
  • submit command examples
  • get command examples
  • checkout command usage
  • sync command workflow
  • Stacked PR workflow guide
• Create CONTRIBUTING.md - Development guide
• Document test organization (unit/integration/e2e)
• Document how to add new commands with tests
• Add architecture overview (metadata, GitHub client)
• Add troubleshooting guide
• Add FAQ section
• Document environment variables (GITHUB_TOKEN, etc.)

CI Pipeline Enhancements

• Configure pytest-xdist for parallel test execution
• Add test job matrix:
  • Python versions: 3.10, 3.11, 3.12, 3.13, 3.14
  • OS: Ubuntu, macOS, Windows
  • Git versions: 2.30+, latest
• Add coverage reporting with codecov
• Add coverage badge to README
• Add test result summary to PR comments
• Configure dependabot for dependency updates
• Add performance benchmarking job
• Add linting job (ruff)
• Add type checking job (mypy, if applicable)
• Run e2e test script in CI

Release Preparation

• Add CHANGELOG.md
• Document versioning scheme (semver)
• Add release workflow (GitHub Actions)
• Prepare v1.0.0 release notes

Code Quality

• Ensure 90%+ test coverage
• Add type hints to all functions
• Document all public APIs
• Add docstrings where missing

Acceptance Criteria

• Documentation complete and accurate
• CI tests run on all supported platforms
• Coverage >90% and tracked in CI
• All code properly documented
• Release process documented
• Contributing guide helps new developers

Start by reviewing README.md and the unchecked checklist, then separate the documentation, CI, release, and code-quality tasks into focused changes. The named deliverables include TESTING.md, CONTRIBUTING.md, CHANGELOG.md, updated README.md content, CI workflows, and release notes; done means the applicable acceptance criteria are met.