feat(layered-products): trigger build on artc cluster via --on-cluster

[ashwindasr]

Summary

• Add `--on-cluster` to the `artcd build-layered-products` command so the Jenkins job triggers the `build-layered-products` Tekton PipelineRun in the `layered-products` namespace on the artc cluster, blocking until completion with logs streamed to the Jenkins console (via `tkn pipeline start --showlog`)
• Add `art-cluster-layered-products-pipeline-kubeconfig` Jenkins credential binding (exposes `ART_CLUSTER_LAYERED_PRODUCTS_KUBECONFIG` env var)
• Remove `returnStdout: true` from `sh()` so `tkn --showlog` output flows to the Jenkins build log

All existing credentials are retained unchanged.

Pre-requisites

A Jenkins credential `art-cluster-layered-products-pipeline-kubeconfig` must be created (file type) containing a kubeconfig for a ServiceAccount in the `layered-products` namespace with permission to create/watch PipelineRuns.

Companion PRs

• art-tools (adds `--on-cluster` option): feat(pyartcd): add on-cluster trigger mode for build-layered-products art-tools#3316
• art-config (new `layered-products` namespace + Tekton pipeline on artc): https://github.com/openshift-eng/art-config/pull/166

Test plan

• Confirm `art-cluster-layered-products-pipeline-kubeconfig` credential exists in Jenkins
• Run a dry-run build and verify a PipelineRun is created in the `layered-products` namespace on artc
• Confirm Tekton logs stream to the Jenkins console
• Confirm build result reflects the PipelineRun outcome

Made with Cursor

[openshift-ci]

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