Summary

Move Kiro from B tier ("test if time permits") to S tier ("test always") in the tool support tiers.

Current state

Kiro is currently in B tier alongside Roo Code, amp, and pi. However, agnix already has dedicated Kiro rules (kiro-001 through kiro-004, kr-sk-001), Kiro is listed in the website's supported tools, and it's included in siteData.json unique tools.

What needs to happen

• Update CLAUDE.md / AGENTS.md tool support tiers to list Kiro under S tier
• Add Kiro to the Supported Tools table in README.md (currently missing despite having rules)
• Ensure Kiro configs are covered in CI test matrix at the same level as Claude Code, Codex CLI, and OpenCode
• Add any missing real-world test fixtures for Kiro