helm: add Kubeflow Notebooks chart

[danish9039]

Summary of Changes

Adds the Kubeflow Notebooks v1 Helm wrapper chart as a co-located application chart under applications/notebooks-v1/helm.

This PR keeps the first reviewable slice focused on Kustomize parity for the customer-facing Notebooks platform install path. It retains the platform scenario, which maps to applications/notebooks-v1/overlays/istio, and does not introduce standalone, split-component, or broad customization modes in this initial chart PR.

The PR also updates Helm/Kustomize comparison wiring to the new chart path, uses Helm 4 in the comparison workflow, and extends scripts/synchronize-notebooks-v1-manifests.sh so future Notebooks upstream syncs also refresh the Helm chart appVersion and regenerated static platform template.

The chart is placed under applications/notebooks-v1/helm because Notebooks v1 is an official application component, and this is the application-side equivalent of placing common wrappers under common/<component>/helm. The sync script owns applications/notebooks-v1/upstream, while the Helm chart lives as a sibling under applications/notebooks-v1/helm.

Dependencies

Conceptually follows the foundation, wrapper, and Dashboard chart PRs for runtime installation order:

• helm: add Kubeflow foundation charts #3468
• helm: add cert-manager wrapper chart #3470
• helm: add Istio wrapper chart #3478
• helm: add oauth2-proxy wrapper chart #3479
• helm: add Dex wrapper chart #3480
• helm: add Kubeflow Dashboard chart #3524

Render parity validation for this PR is self-contained.

Related Issues

Part of the Project 5 Helm chart work.

Contributor Checklist

• I have tested these changes with kustomize. See Installation Prerequisites.
• All commits are signed-off to satisfy the DCO check.
• I have considered adding my company to the adopters page to support Kubeflow and help the community, since I expect help from the community for my issue (see 1. and 2.).

Validation

helm lint applications/notebooks-v1/helm
./tests/helm_kustomize_compare.sh kubeflow-notebooks platform
./tests/helm_kustomize_compare_all.sh kubeflow-notebooks
bash -n scripts/synchronize-notebooks-v1-manifests.sh tests/helm_kustomize_compare.sh tests/helm_kustomize_compare_all.sh
python3 -m py_compile tests/helm_kustomize_compare.py
git diff --check

Also verified with temporary Helm v4.2.2:

helm lint applications/notebooks-v1/helm
./tests/helm_kustomize_compare_all.sh kubeflow-notebooks

[google-oss-prow]

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[github-actions]

Welcome to the Kubeflow Community Distribution Repository

Thanks for opening your first PR. Your contribution means a lot to the Kubeflow community.

Before making more PRs:
Please ensure your PR follows our Contributing Guide.
Please also be aware that many components are synchronized from upstream via the scripts in /scripts.
So in some cases you have to fix the problem in the upstream repositories first, but you can use a PR against kubeflow/community-distribution to test the platform integration.

Community Resources:

• CNCF Slack channels: https://www.kubeflow.org/docs/about/community/#kubeflow-slack-channels
• Community meetings: https://www.kubeflow.org/docs/about/community/

Thanks again for helping to improve Kubeflow.

[Copilot]

Pull request overview

Adds a co-located Helm wrapper chart for Kubeflow Notebooks v1 under applications/notebooks-v1/helm, and wires it into the existing Helm/Kustomize render-parity comparison and synchronization workflow so future upstream refreshes also regenerate the chart payload.

Changes:

• Introduce kubeflow-notebooks Helm wrapper chart (static Kustomize-parity “platform” scenario).
• Extend Helm/Kustomize comparison scripts to include the new kubeflow-notebooks component/scenario.
• Update the Notebooks v1 synchronization script and CI workflow to keep the chart’s appVersion and rendered platform template refreshed (and to install Helm v4.2.2 for the comparison job).

Reviewed changes

Copilot reviewed 10 out of 11 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
applications/notebooks-v1/helm/Chart.yaml	New chart metadata for kubeflow-notebooks.
applications/notebooks-v1/helm/README.md	Installation and parity-comparison instructions for the new chart.
applications/notebooks-v1/helm/values.yaml	Default values, including the scenario switch.
applications/notebooks-v1/helm/ci/values-platform.yaml	CI fixture values for the platform scenario.
applications/notebooks-v1/helm/templates/platform.yaml	Generated static template containing the platform render payload.
applications/notebooks-v1/helm/templates/validate.yaml	Scenario validation guardrail for supported values.
tests/helm_kustomize_compare.sh	Adds kubeflow-notebooks wiring (chart path, kustomize overlay, values, namespace).
tests/helm_kustomize_compare_all.sh	Adds kubeflow-notebooks to the “all components” scenario matrix and help text.
tests/helm_kustomize_compare.py	Allows kubeflow-notebooks as a recognized component in the comparison tool.
scripts/synchronize-notebooks-v1-manifests.sh	Extends sync to also update chart appVersion and regenerate templates/platform.yaml.
.github/workflows/helm-kustomize-comparison.yml	Triggers on Notebooks changes and installs Helm v4.2.2 for parity checks.

[danish9039]

Fixed by preserving Notebooks app labels.

[Copilot]

Pull request overview

Copilot reviewed 10 out of 11 changed files in this pull request and generated 1 comment.