curl --request GET \
  --url http://localhost:8000/issuers/lookup/ruc

{
  "valid": true,
  "ruc": "<string>",
  "legal_name": "<string>",
  "trade_name": "<string>",
  "address": "<string>",
  "contributor_status": "<string>",
  "contributor_type": "<string>",
  "legal_representative_name": "<string>",
  "sri_data": {},
  "error": "<string>",
  "establishments": [
    {
      "number": "<string>",
      "is_matrix": true,
      "type": "<string>",
      "name": "<string>",
      "address": "<string>",
      "status": "<string>",
      "sri_data": {}
    }
  ]
}