chore(workflow): add PR labeler

[chenjiahan]

Summary

Add PR labeler to workflow (the same as Rspack/Rsbuild/Rsdoctor), this allows to:

• add label for PR
• generate CHANGELOG via GitHub release.

Checklist

• [ ] I have added changeset via pnpm run change.
• [ ] I have updated the documentation.
• [ ] I have added tests to cover my changes.

[netlify[bot]]

✅ Deploy Preview for rsdoctor ready!

Name	Link
🔨 Latest commit	7f181a6571dab89d35f342d39de89dff87f9908f
🔍 Latest deploy log	https://app.netlify.com/sites/rsdoctor/deploys/660d24d06366ff00081afefa
😎 Deploy Preview	https://deploy-preview-276--rsdoctor.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.