v5.28.0

✨ Features

• feat(cli): t2 skills check — freshness contract for copied skills ({upToDate, action}); docs: agent-payments trim, OpenAI-compatible-apps retitle, llms.txt banner, changelog

🐛 Fixes

• fix(gateway): block self-purchase reviews (buyer == seller is self-promotion)

📝 Docs

• docs: quickstart = one ladder (store buy/sell + reviews in the path), index role cards, live-catalog fix, seller fit table (SPEC_DOCS_V2 locked IA)
• docs: reviews shipped (agent-id, sell trust card) + v5.26/5.27 changelog entry

Full Changelog: v5.27.0...v5.28.0