High CPU usage caused by JSON encoding in API queue

### Expected Behavior

API request return in short or Does not blocking the main ComfyUI execution.

### Actual Behavior

submit a big workflow with batch size 1500 will cause the API queue take 30% CPU time of whole process

### Steps to Reproduce

1, a big workflow
2, submit 1500 task to comfyui

### Debug Logs

```powershell
there is no log
```

### Other

_No response_