Copilot code review cleanup job fails deleting artifacts with 403

Summary

GitHub Actions run 23775280758 is currently failing in workflow Copilot code review, job Cleanup artifacts, step Delete artifacts.

• Run URL: https://github.com/karpathy/autoresearch/actions/runs/23775280758
• Failing job URL: https://github.com/karpathy/autoresearch/actions/runs/23775280758/job/69276000639
• Branch ref: efs/pull/453/head

Error snippet

ext gh: Resource not accessible by integration (HTTP 403) Process completed with exit code 1.

Likely root-cause bucket

Workflow token permissions / integration scope mismatch during artifact deletion.

Smallest safe next steps

• Inspect the token permissions available to the cleanup job.
• Compare artifact deletion permissions with the workflow's current permissions: block.
• Decide whether cleanup should be best-effort instead of fail-fast.