api 服务 /v1/assistants/lite 接口，调用后无法使用stream模式

[limi1]

Initial Checks

• [ ] I have searched GitHub for a duplicate issue and I'm sure this is something new
• [X] I have read and followed the docs & demos and still think this is a bug
• [ ] I am confident that the issue is with modelscope-agent (not my code, or another library in the ecosystem)

What happened + What you expected to happen

Versions / Dependencies

master分支

Reproduction script

启动assistant_server_api即可

Issue Severity

Low: It annoys or frustrates me.

[limi1]

Response中的media_type 不是text/event-stream