Support OCI artifact for the helm charts

[cthtrifork]

Is your feature request related to a problem? Please describe.
I prefer installing helmcharts through
https://fluxcd.io/flux/components/source/ocirepositories/

There is a trend of storing helm charts as OCI artifacts.

Storing Helm charts in OCI registries alongside container images offers several advantages:

• Signed charts — All charts are signed with cosign for verification
• Simpler setup — No repository configuration needed
• Digest pinning — Reference exact chart versions by SHA for reproducibility
• Unified tooling — Use the same registry infrastructure for images and charts

Describe the solution you'd like
So we would need something like:

helm registry login ghcr.io -u ${{ github.actor }} -p ${{ secrets.GITHUB_TOKEN }}
echo "PACKAGE_PATH=$(helm package . | awk '{print $NF}')" >> $GITHUB_ENV
helm push ${{ env.PACKAGE_PATH }} oci://ghcr.io/$GITHUB_REPOSITORY_OWNER

to ensure its on ghcr.io.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
What’s important to note is that the an OCIRepository can be reused across multiple HelmRelease resources, which is useful when deploying multiple microservices using the generic Helm chart.

I dont mind implementing this, if there is support

[cthtrifork]

It was originally created here:
#1755

but closed by a bot without a comment from maintainers. So I needed to try again to gain a discussion.

[sudermanjr]

At the moment we do not have the bandwidth to support building this. I'll leave it open as a request, but we will not be able to prioritize it.

Since it will require changes to our internal infrastructure, I don't believe we can support an external contribution for this either.

[sudermanjr]

For future reference if we come back to this - we currently have signing via cosign for images that we push to google artifact registry. Likely we would utilize that rather than GHCR since we don't use that anywhere else.