Repository: stable-diffusion-webui
Issue: [Bug]: Extension path error after moving and renaming WebUI dir
Labels: bug-report

### Checklist

- [ ] The issue exists after disabling all extensions
- [ ] The issue exists on a clean installation of webui
- [X] The issue is caused by an extension, but I believe it is caused by a bug in the webui
- [X] The issue exists in the current version of the webui
- [ ] The issue has not been reported before recently
- [ ] The issue has been reported before but has not been fixed yet

### What happened?

The extension `sd-webui-animatediff` not working due to a path error, I traced some code and found this part, I suspect this is the root cause.

In `animatediff_mm.py`
```python
    def get_model_dir(self):
        model_dir = shared.opts.data.get("animatediff_model_path", os.path.join(self.script_dir, "model"))
        if not model_dir:
            model_dir = os.path.join(self.script_dir, "model")
        return model_dir
```

Where can I specify or reset the `animatediff_model_path` in `shared.opts.data` ?

p.s. Actually, I have a lot of extensions, but only this causes errors.

### Steps to reproduce the problem

1. Install `sd-webui-animatediff` from any source (WebUI, git pull, etc...)
2. Execute `webui-user.bat`

### What should have happened?

The extension needs to be working.

### What browsers do you use to access the UI ?

Google Chrome

### Sysinfo

[sysinfo-2024-04-14-04-53.json](https://github.com/AUTOMATIC1111/stable-diffusion-webui/files/14969531/sysinfo-2024-04-14-04-53.json)


### Console logs

```Shell
*** Error calling: C:\Users\ytc\Desktop\StabilityMatrix-win-x64\Data\Packages\Stable Diffusion WebUI\extensions\sd-webui-animatediff\scripts\animatediff.py/ui
    Traceback (most recent call last):
      File "C:\Users\ytc\Desktop\StabilityMatrix-win-x64\Data\Packages\Stable Diffusion WebUI\modules\scripts.py", line 547, in wrap_call
        return func(*args, **kwargs)
      File "C:\Users\ytc\Desktop\StabilityMatrix-win-x64\Data\Packages\Stable Diffusion WebUI\extensions\sd-webui-animatediff\scripts\animatediff.py", line 45, in ui
        unit = AnimateDiffUiGroup().render(
      File "C:\Users\ytc\Desktop\StabilityMatrix-win-x64\Data\Packages\Stable Diffusion WebUI\extensions\sd-webui-animatediff\scripts\animatediff_ui.py", line 290, in render
        model_list = self.get_model_list()
      File "C:\Users\ytc\Desktop\StabilityMatrix-win-x64\Data\Packages\Stable Diffusion WebUI\extensions\sd-webui-animatediff\scripts\animatediff_ui.py", line 259, in get_model_list
        os.mkdir(model_dir)
    FileNotFoundError: [WinError 3] The system cannot find the path specified.: 'C:\\Users\\ytc\\Desktop\\stable-diffusion-webui_v1.6.0_t1.13.1\\extensions\\sd-webui-animatediff\\model'
```


### Additional information

I moved and renamed my WebUI folder, and I also installed `sd-webui-animatediff` before but I removed it by deleting the whole directory, now while I install it, it will cause a path error.

Before move : `Desktop/stable-diffusion-webui_v1.6.0_t1.13.1`
After move : `Desktop/StabilityMatrix-win-x64\Data\Packages\Stable Diffusion WebUI`