curl --request POST \
  --url https://api.zatten.com/api/v1/messages/image \
  --header 'Content-Type: multipart/form-data' \
  --header 'x-api-key: <api-key>' \
  --form 'lead_number=<string>' \
  --form file='@example-file' \
  --form 'caption=<string>'

{
  "wa_id": "<string>",
  "thread_id": "<string>"
}