returns vcluster user agent with a constant name part used by the API server for FieldManager.

DefaultVClusterConfigLocation is the default location of the vCluster config within the container.

IndexByHostName is used to map rewritten hostnames(advertised as node addresses) to nodenames.

IndexRunningNonVClusterPodsByNode is only used when the vcluster scheduler is enabled.

KubeletPort is the port we pretend the kubelet is running under.

NodeSuffix is the dns suffix for our nodes.