### What problem does this PR solve?
Fix some issues in API and test
### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)
Co-authored-by: liuhua <10215101452@stu.ecun.edu.cn>
### What problem does this PR solve?
Fix some issues in API
### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)
---------
Co-authored-by: liuhua <10215101452@stu.ecun.edu.cn>
### What problem does this PR solve?
Refactor Chat API
### Type of change
- [x] Refactoring
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Co-authored-by: liuhua <10215101452@stu.ecun.edu.cn>
liuhua