OpenAI SDK → Chinese LLMs

Before

client = OpenAI(api_key=OPENAI_KEY)

After

client = OpenAI(
    api_key=CHINASO_KEY,
    base_url="https://api.chinaso.org/v1",
)

Swap the model string to deepseek-chat or qwen-plus. Streaming and tool-calling work when the upstream model supports them.