docs: add extensive code review of CodeInput CLI

Comprehensive review covering:
- Project architecture and workspace organization
- Code quality analysis with specific issues identified
- Error handling patterns and recommendations
- Test coverage gaps (critical: missing CLI tests)
- Security analysis
- Performance optimizations
- API design evaluation
- Dependency analysis

Key findings:
- Critical: Library code panics on invalid patterns (should return Result)
- Critical: Hash calculation is broken (acknowledged in TODO)
- High: Multiple unwrap() calls that could panic
- Missing: Integration tests for CLI commands
- Performance: O(n*m) complexity in owner/tag collection

Author: claude