curl --request POST \
  --url http://34.170.194.254:8000/api/v1/custody/confirmations \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "message_id": "<string>",
  "timestamp": "2023-11-07T05:31:56Z",
  "event_type": "<string>",
  "address": "<string>",
  "asset": "<string>",
  "custody_account_id": "<string>",
  "quantity": 123,
  "external_metadata": {},
  "idempotency_key": "<string>"
}
'

{
  "custody_confirmation_id": "<string>"
}