The request must be sent as multipart/form-data with required metadata and file fields.

The metadata field is plain text whose value must be valid JSON.

Metadata fields and CSV fields use camelCase names.

Additional CSV columns are allowed and ignored by this endpoint.

When validation fails, the response body contains grouped top-level and row-level errors.

Sample metadata:
{
"reportId": "report-1",
"transferId": "transfer-1",
"currency": "GBP",
"transferDate": "2024-01-01"
}
Sample CSV body:
loan_id,payments_transmitted
11111111-1111-1111-1111-111111111111,123.45