The documentation incorrectly suggested using api.moonshot.cn as an
alternative China endpoint. Testing shows this endpoint returns 401
Invalid Authentication errors even with valid API keys.
The correct global endpoint is api.moonshot.ai/v1, which is already
used in the source code (src/agents/models-config.providers.ts).
Updated the docs to reflect this and removed the misleading note
about the .cn endpoint to prevent user confusion.
