feat: add rust-production-readiness skill

[llbartekll]

Summary

• Adds a new skill for auditing Rust code before production deployment
• Includes automated checks (cargo clippy, cargo audit, cargo test)
• Provides a detailed 10-category manual review checklist

What's included

SKILL.md - Main skill file with:

• Workflow for systematic code audit
• Severity definitions (Critical/High/Medium/Low)
• Report template
• Evaluation prompts

CHECKLIST.md - Detailed checklist covering:

1. Error handling (unwrap, expect, Result propagation)
2. Panic vectors (panic!, unreachable!, indexing)
3. Unsafe code (safety comments, FFI boundaries)
4. Async & concurrency (locks across await, blocking calls)
5. Memory & performance (allocations, cloning)
6. Dependencies (cargo audit, vulnerabilities)
7. API & documentation
8. Testing coverage
9. Configuration & environment (no hardcoded secrets)
10. Build & release readiness

Usage

/rust-production-readiness

Test plan

• Validation passes (./scripts/validate.sh)
• Install and test in a Rust project

🤖 Generated with Claude Code