the task is to add the permanent label k8s_cluster=state to the help chart victoria-metrics-agent, I tried adding it via extraLabels, but it is added only to pod, deployment, etc. vmagent I use helm chart https://github.com/VictoriaMetrics/helm-charts
Have you tried configuring vmagent with the following flag:
/path/to/vmagent -remoteWrite.label=k8s_cluster=state ...
https://docs.victoriametrics.com/vmagent.html#adding-labels-to-metrics