List Kubernetes clusters

Example response

{
  "object": "list",
  "data": [
    {
      "object": "kubernetes_cluster",
      "kubernetes_api_url": "https://cluster.example.com",
      "name": "richmond",
      "kubernetes_namespace": "sf-user123",
      "kubernetes_ca_cert": "-----BEGIN CERTIFICATE-----...",
      "contract": {
        "object": "contract",
        "id": "cont_k3R-nX9vLm7Qp2Yw5Jd8F",
        "created_at": "2025-07-11T20:41:37.423Z",
        "instance_type": "h100i",
        "shape": {
          "intervals": [
            "2025-07-11T20:41:37.423Z"
          ]
        },
        "colocate_with": [
          "cont_k3R-nX9vLm7Qp2Yw5Jd8F"
        ],
        "cluster_id": "clus_k3R-nX9vLm7Qp2Yw5Jd8F",
        "zone": "richmond",
        "is_node": true,
        "procurement_id": "proc_1234567890abcdef"
      }
    }
  ]
}