[Copilot]

The lifecycle remote downstream build failed after Bazel received HTTP 500 fetching rules_go v0.60.0. This change retries once for repository download HTTP 5xx failures while preserving immediate failure for other build errors.

• Retry policy: Retry a failed Bazel command once only when its output reports a repository download HTTP 5xx.
• Coverage: Add focused tests for the retry and for immediate failure on ordinary build errors.

if "Download from " in line and re.search(r"GET returned 5\d{2}", line):
    retryable_download_error = True

🚨 Impact Analysis

• This change does not violate any tool requirements and is covered by existing tool requirements
• This change does not violate any design decisions
• Otherwise I have created a ticket for new tool qualification

✅ Checklist

• Added/updated documentation for new or changed features
• Added/updated tests to cover the changes
• Followed project coding standards and guidelines