feat: add AI agent workflow for automated code review

[zubeyralmaho]

What:

Adds an AI-powered code review system using Claude Opus 4 that automatically analyzes PRs.

Why:

• Automates code review for faster feedback
• Catches common issues (React best practices, PropTypes, security vulnerabilities)
• Provides consistent test coverage analysis
• Reduces review burden on maintainers

How:

• GitHub Actions workflow runs 3 agents in parallel on PR events
• Code Review Agent: Analyzes React patterns and PropTypes
• Testing Agent: Reviews test coverage and suggests improvements
• Security Agent: Runs npm audit and checks for vulnerabilities
• Results posted as a single PR comment

Setup: Add ANTHROPIC_API_KEY to repository secrets.

Checklist:

• Documentation added to the docs site
• Tests
• Ready to be merged