PR-Summary Skill

When invoked:

1. Inspect active git diff main...HEAD and review completed items in .agents/state.json.
2. Generate Markdown output formatted for GitHub Pull Requests.
3. Structure output with:
   • Summary: Concise overview of changes.
   • Key Architectural Changes: Structural modifications or new abstractions.
   • Testing Verification: Proof of passed unit test suites and type-checks.
   • Breaking Changes: Any breaking API or schema updates.