It's not obvious that a load balancer is required for HA

[jbergler]

Is your feature request related to a problem? Please describe.

I know it's documented, but when I read the docs the first time I missed the nuance about control plane connectivity issues without having a tcp load balancer and spent quite a while debugging konnectivity-agent "duplicate server" errors.

Describe the solution you would like

It would be awesome if k0sctl required either spec.api.externalAddress or spec.network.nodeLocalLoadBalancing to be set when there are multiple controllers defined for the cluster. If there are valid deployments without a load balancer then maybe a warning during apply would be sufficient.

Describe alternatives you've considered

No response

Additional context

None, just wanted to say thanks for what is a great project!