Adds Audit Skill — a comprehensive audit toolkit with 14 audit types for Claude Code.

What it does:

• Branch audit (default): pre-push review with 8-category checklist producing Clean/Minor/Blocking verdicts
• 13 deep-dive audits via sub-agents: code quality, docs brittleness, docs-code sync, language best practices, concurrency, resource management, test quality, feature completeness, performance, bug patterns, design philosophy, security, and UI design

Category: Development & Code Tools (alphabetical placement between artifacts-builder and aws-skills)