[abice]

Summary

The consumer-gen-mcp coverage job fails when Docker Hub returns HTTP 429 for golang:1.21. Pull the same Go base image from Google's public mirror without registry credentials.

Jira: https://rewardstyle.atlassian.net/browse/BRE-5079 (BRE-4026, 1 point).
Failure: https://github.com/rewardStyle/consumer-gen-mcp/actions/runs/37988460677/job/114026709169

Changes

• Use mirror.gcr.io/library/golang:1.21 in the Dockerfile.
• Run the integration self-test against the checked-out action so hosted CI builds and exercises this Dockerfile.
• Repair existing dependency-review YAML indentation and its broken action repository reference so its check can run.

Testing

• Unauthenticated mirror manifest request returned HTTP 200.
• git diff --check passed.
• GOMAXPROCS=2 go test -p 1 ./interval passed with a temporary writable build cache.
• Docker builds and the full suite are reserved for hosted CI because of local disk pressure.
• Hosted integration CI built the image from the mirror, passed the full Go suite, and passed the action self-test on head 326a6f350c92f86a8a8d44a239c1992e4ae2fcdd: https://github.com/rewardStyle/cov-diff/actions/runs/37992922673.
• Dependency review, CodeQL, and all visible Wiz checks passed on the same head.

Risks

Google's public mirror is a cache; availability of a particular tag is not guaranteed indefinitely.
KTL review is unavailable because this repository has no KTL workflow configured.

[github-actions]

Coverage on new code: 100%