curl --request POST \
  --url https://app.herondata.io/api/end_users/{end_user_id_or_heron_id}/files \
  --header 'Content-Type: application/json' \
  --header 'x-api-key: <api-key>' \
  --data '
{
  "file_base64": "<string>",
  "filename": "<string>",
  "file_class": "<string>",
  "reference_id": "<string>",
  "trigger_downstream_processing": true
}
'

{
  "bank_statement": null,
  "created": "2023-11-07T05:31:56Z",
  "email": null,
  "file_class": "<string>",
  "file_source_metadata": {},
  "filename": "<string>",
  "heron_id": "<string>",
  "iso_application": {
    "heron_id": "iso_6hBjQT9k6KP2rLCXwjUJff",
    "processing_status": "processed"
  },
  "num_pages": 123,
  "page_classes": {},
  "parent_heron_id": "<string>",
  "parsed_results": [],
  "reference_id": "<string>",
  "renamed_filename": "<string>"
}