make helm part of the system packages

[obeleh]

There are a few helm implementations I saw in this discussion it would be nice if helm would have been a built-in package of KCL. In fact, if I would make a feature (wish)list, this would be definitely on top.

helm.template(
    chart="example",
    target_revision="0.1.0",
    repo_url="https://example.com/charts",
)

It would bring KCL to a more central place in my tooling to render YAML. Right now I'm calling both KCL and Helm from Taskfiles. But it would be nice to have KCL build everything

@zong-zhe