code: func makeInstanceGroupName(clusterID string) string {
  	prefix := "k8s-ig"
  	// clusterID might be empty for legacy clusters
  	if clusterID == "" {
  		return prefix
  	}
  	return fmt.Sprintf("%s--%s", prefix, clusterID)
  }
docs: // Internal Load Balancer
  // Instance groups remain legacy named to stay consistent with ingress