Offboard site and assets

curl --request POST \
  --url https://api-sandbox.axle.energy/entities/site/{site_id}/offboard-site-and-assets \
  --header 'Authorization: Bearer <token>'

{
  "site": {
    "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
    "mpan": "<string>",
    "postcode": "<string>",
    "address": "<string>",
    "asset_ids": [],
    "markets": [
      "cm"
    ],
    "dispatch_methods": [
      "cm_infrequent_dispatch"
    ],
    "tariff": {
      "tariff_type": "single_rate",
      "tariff_cheap_start_time": "<string>",
      "tariff_cheap_end_time": "<string>"
    },
    "gave_boundary_meter_consent_at": "2023-11-07T05:31:56Z"
  },
  "asset": {
    "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
    "external_id": "<string>",
    "type": "boundary meter",
    "site_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
    "properties": {
      "power_kw": 1,
      "capacity_kwh": 1
    }
  }
}