curl --location '{{baseUrl}}/api/whatsapp/get-variable-by-template-id/123456789012345/987654321' \
--header 'Authorization: Bearer {{authToken}}'

{
  "status": true,
  "code": 200,
  "message": "Template variables fetched successfully",
  "data": {
    "templateId": "987654321",
    "templateName": "appointment_reminder",
    "variables": [
      {
        "name": "customer_name",
        "type": "string"
      },
      {
        "name": "appointment_date",
        "type": "string"
      },
      {
        "name": "appointment_time",
        "type": "string"
      }
    ]
  }
}