OpenAI 聊天补全

{
  "model": "MODEL_NAME",
  "messages": [
    {
      "role": "system",
      "content": "你是一个专业、准确的助手。"
    },
    {
      "role": "user",
      "content": "用三句话解释 AnyRoute API 的用途"
    }
  ],
  "stream": true
}