Windows file picker defaults to PNG Image filter instead of Custom Files in native upload dialogs

### 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

The dialog should default to the aggregate filter (Custom Files) so that all supported file types are visible immediately, rather than opening on PNG only.

### Actual Behavior

In ComfyUI file-open dialogs, the filter list appears as:

PNG Image (*.png)
JPG File (*.pjp;*.jfif;*.pjpeg;*.jpeg;*.jpg)
WEBP File (*.webp)
Custom Files (...)
All Files (*.*)

### Steps to Reproduce

Open any image upload dialog box

Reproduces on Windows 11 with ComfyUI 0.18.1 / Frontend 1.42.10 even when launched with --disable-all-custom-nodes

### Debug Logs

```powershell
(venv active)

(venv) J:\Comfyui_LTX\ComfyUI>python main.py --disable-all-custom-nodes
J:\Comfyui_LTX\ComfyUI\venv\Lib\site-packages\torch\cuda\__init__.py:63: FutureWarning: The pynvml package is deprecated. Please install nvidia-ml-py instead. If you did not install pynvml directly, please report this to the maintainers of the package that installed pynvml for you.
import pynvml # type: ignore[import]
WARNING: You need pytorch with cu130 or higher to use optimized CUDA operations.
Found comfy_kitchen backend cuda: {'available': True, 'disabled': True, 'unavailable_reason': None, 'capabilities': ['apply_rope', 'apply_rope1', 'dequantize_nvfp4', 'dequantize_per_tensor_fp8', 'quantize_mxfp8', 'quantize_nvfp4', 'quantize_per_tensor_fp8']}
Found comfy_kitchen backend triton: {'available': True, 'disabled': True, 'unavailable_reason': None, 'capabilities': ['apply_rope', 'apply_rope1', 'dequantize_nvfp4', 'dequantize_per_tensor_fp8', 'quantize_mxfp8', 'quantize_nvfp4', 'quantize_per_tensor_fp8']}
Found comfy_kitchen backend eager: {'available': True, 'disabled': False, 'unavailable_reason': None, 'capabilities': ['apply_rope', 'apply_rope1', 'dequantize_mxfp8', 'dequantize_nvfp4', 'dequantize_per_tensor_fp8', 'quantize_mxfp8', 'quantize_nvfp4', 'quantize_per_tensor_fp8', 'scaled_mm_mxfp8', 'scaled_mm_nvfp4']}
Checkpoint files will always be loaded safely.
Total VRAM 24564 MB, total RAM 130861 MB
pytorch version: 2.9.1+cu128
Set vram state to: NORMAL_VRAM
Device: cuda:0 NVIDIA GeForce RTX 4090 : cudaMallocAsync
Using async weight offloading with 2 streams
Enabled pinned memory 52344.0
working around nvidia conv3d memory bug.
Using pytorch attention
aimdo: src-win/cuda-detour.c:77:INFO:aimdo_setup_hooks: found driver at 00007FF8C6210000, installing 4 hooks
aimdo: src-win/cuda-detour.c:61:DEBUG:install_hook_entrys: hooks successfully installed
aimdo: src/control.c:69:INFO:comfy-aimdo inited for GPU: NVIDIA GeForce RTX 4090 (VRAM: 24563 MB)
DynamicVRAM support detected and enabled
Python version: 3.12.7 | packaged by Anaconda, Inc. | (main, Oct 4 2024, 13:17:27) [MSC v.1929 64 bit (AMD64)]
ComfyUI version: 0.18.1
comfy-aimdo version: 0.2.12
comfy-kitchen version: 0.2.8
ComfyUI frontend version: 1.42.10
[Prompt Server] web root: J:\Comfyui_LTX\ComfyUI\venv\Lib\site-packages\comfyui_frontend_package\static
Asset seeder disabled
Skipping loading of custom nodes
Context impl SQLiteImpl.
Will assume non-transactional DDL.
Starting server

To see the GUI go to: http://127.0.0.1:8188
```

### Other

This affects usability because users must manually switch the dropdown each time to see the full supported file set.
No Windows file association corruption was found in .png / .jpg associations during testing.

This appears to be specific to how ComfyUI constructs or orders file dialog filters on Windows native dialogs.