curl --request POST \
  --url https://api.meetcampfire.com/rr/api/v1/contracts/{contract_id}/usage \
  --header 'Authorization: <api-key>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "contract": 123,
  "product": 123,
  "usage_group": 123,
  "department": 123,
  "tags": "<string>",
  "description": "<string>",
  "start_date": "2023-12-25",
  "end_date": "2023-12-25"
}
'

{
  "id": 123,
  "contract": 123,
  "product_bundle": "<string>",
  "contract_product_bundle": {
    "id": 123,
    "source_bundle_name": "<string>",
    "total_amount": 0,
    "lines": [
      {
        "id": 123,
        "product": 123,
        "product_name": "<string>",
        "amount": 0,
        "percentage": "<string>",
        "original_percentage": 0
      }
    ],
    "source_bundle": 123,
    "currency": "<string>"
  },
  "product_name": "<string>",
  "product_bundle_name": "<string>",
  "usage_group_name": "<string>",
  "lines": "<string>",
  "created_at": "2023-11-07T05:31:56Z",
  "last_modified_at": "2023-11-07T05:31:56Z",
  "product": 123,
  "usage_group": 123,
  "department": 123,
  "tags": "<string>",
  "description": "<string>",
  "start_date": "2023-12-25",
  "end_date": "2023-12-25"
}