V3 nodes COMBO widget are incompatible with older version of the UI (using the argument "--front-end-root")

### 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

Nodes like KSamplerSelect showing the list of samplers.

### Actual Behavior

Some nodes shows "C O M B O" as the options and the default is "undefined".

Here with KSamplerSelect:

Also happens with AlignYourStepsScheduler:

But not with some others:

(which, I just checked, is not V3 yet)

### Steps to Reproduce

using the argument --front-end-root path/to/web_folder

With the web folder from commit [82ecb02c1ed29455047dcaa3839497b2cfa92852](https://github.com/comfyanonymous/ComfyUI/tree/82ecb02c1ed29455047dcaa3839497b2cfa92852)

### Debug Logs

```powershell
Checkpoint files will always be loaded safely.
Total VRAM 12281 MB, total RAM 49072 MB
pytorch version: 2.8.0+cu128
Set vram state to: NORMAL_VRAM
Device: cuda:0 NVIDIA GeForce RTX 4070 : cudaMallocAsync
Using async weight offloading with 2 streams
Enabled pinned memory 22082.0
Using pytorch attention
Python version: 3.10.9 | packaged by Anaconda, Inc. | (main, Mar 1 2023, 18:18:15) [MSC v.1916 64 bit (AMD64)]
ComfyUI version: 0.3.75
[Prompt Server] web root: C:\StableDiffusion\workingwebui\comfyui\web
C:\anaconda3\envs\comfy\lib\site-packages\pydantic\_internal\_fields.py:161: UserWarning: Field "model_url" has conflict with protected namespace "model_".

You may be able to resolve this warning by setting `model_config['protected_namespaces'] = ()`.
warnings.warn(
Total VRAM 12281 MB, total RAM 49072 MB
pytorch version: 2.8.0+cu128
Set vram state to: NORMAL_VRAM
Device: cuda:0 NVIDIA GeForce RTX 4070 : cudaMallocAsync
Using async weight offloading with 2 streams
Enabled pinned memory 22082.0
C:\anaconda3\envs\comfy\lib\site-packages\pydantic\_internal\_fields.py:161: UserWarning: Field "model_name" has conflict with protected namespace "model_".

You may be able to resolve this warning by setting `model_config['protected_namespaces'] = ()`.
warnings.warn(
C:\anaconda3\envs\comfy\lib\site-packages\pydantic\_internal\_fields.py:161: UserWarning: Field "model_params" has conflict with protected namespace "model_".

You may be able to resolve this warning by setting `model_config['protected_namespaces'] = ()`.
warnings.warn(
C:\anaconda3\envs\comfy\lib\site-packages\pydantic\_internal\_fields.py:161: UserWarning: Field "model_version" has conflict with protected namespace "model_".

You may be able to resolve this warning by setting `model_config['protected_namespaces'] = ()`.
warnings.warn(
C:\anaconda3\envs\comfy\lib\site-packages\pydantic\_internal\_fields.py:161: UserWarning: Field "model_seed" has conflict with protected namespace "model_".

You may be able to resolve this warning by setting `model_config['protected_namespaces'] = ()`.
warnings.warn(
Skipping loading of custom nodes
Context impl SQLiteImpl.
Will assume non-transactional DDL.
No target revision found.
comfyui-embedded-docs package not found
Starting server

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

### Other

_No response_