docs: guideline against AI-generated PRs

.github/PULL_REQUEST_TEMPLATE.md

@@ -23,3 +23,4 @@ Closes #(issue)
 ## Requirements / 要求
 
 - [ ] I have read and follow the [Code of Conduct](../docs/CODE_OF_CONDUCT.md) and [Contributing Guide](../CONTRIBUTING.md) . / 我已阅读并遵守行为准则。
+- [ ] This PR is NOT generated by a bot or AI agent acting autonomously. I have authored or meaningfully reviewed every change. / 此 PR 不是由 bot 或 AI 自主生成的，我已亲自编写或充分审查了每一处变更。

CONTRIBUTING.md

@@ -188,6 +188,7 @@ Ask an AI to help you add documentation to the `website/` package. Follow the ex
 - Contributions without proper testing
 - Code that doesn't follow project conventions
 - Dependencies or code with licenses incompatible with MIT
+- Bot or AI-generated pull requests without meaningful human involvement
 
 ## 📄 Legal