SDXL model saving issue

### Custom Node Testing

- [x] I have tried disabling custom nodes and the issue persists (see [how to disable custom nodes](https://docs.comfy.org/troubleshooting/custom-node-issues#step-1%3A-test-with-all-custom-nodes-disabled) if you need help)

### Expected Behavior

When saving SDXL checkpoint with either "Save Checkpoint" or "Model Save" node, the output model should have the same size as the input one.

### Actual Behavior

After saving, the model's size gets reduced to 4.78 GB. I suspect that clip G gets lost during saving.

### Steps to Reproduce

[BUGGED.json](https://github.com/user-attachments/files/25063077/BUGGED.json)
Siply load and save SDXL checkpoint

### Debug Logs

```powershell
got prompt
Prompt executed in 17.43 seconds
```

### Other

_No response_