curl --request GET \
  --url https://api.valyx.com/invoice/attachments \
  --header 'X-Valyx-Attachment-Upload-Signature: <x-valyx-attachment-upload-signature>'

{
  "error": "<string>",
  "message": "<string>",
  "data": {
    "invoiceId": "<string>",
    "invoiceNumber": "<string>",
    "customerName": "<string>",
    "buyerId": "<string>",
    "attachments": [
      {
        "filename": "<string>",
        "purpose": "<string>",
        "createdAt": "<string>"
      }
    ]
  }
}