Handle transient copilot reviewer job failure caused by GitHub Actions service outage

[Copilot]

Description

The copilot-pull-request-reviewer job failed before workflow steps executed. Root cause was a GitHub Actions platform-side outage (Service Unavailable) while resolving action download metadata for run 31119009568 / job 92675373226.

• Failure analysis

  • Job failed in setup, not in repository code or workflow logic.
  • Error was repeated action-resolution failure from GitHub infrastructure.

• PR scope

  • No application/workflow code changes are required for this failure mode.
  • Recommended remediation is re-run when Actions service recovers.

Failed to resolve action download info. Error: Service Unavailable
##[error]Service Unavailable
##[error]Failed to resolve action download info.

Test (if applicable)

N/A — no code changes in repository; failure is external to repo code.