curl --request GET \
  --url https://api.merchantops.ai/api/lakehouse/documents/{document_id}/mapping

{
  "ambiguous_mappings": [
    "<string>"
  ],
  "available_columns": [
    "<string>"
  ],
  "column_mapping": {},
  "confidence": 123,
  "document_id": "<string>",
  "filename": "<string>",
  "is_valid": true,
  "missing_required_fields": [
    "<string>"
  ],
  "validated_at": "<string>",
  "warnings": [
    "<string>"
  ],
  "file_analysis": {
    "policy_notes": [],
    "recommended_sheets": [],
    "sheet_groups": [],
    "sheets": [],
    "skip_sheets": [],
    "template_brand_key": "<string>",
    "template_found": false
  },
  "recalled_field_rules": {}
}