I hope add --path-prefix args, like tensorboard.

### Feature Idea

I want to add url prefix:

```bash
python main.py --listen 0.0.0.0
```

when open:

```bash
http://10.1.1.29:8188/
```

add url prefix after:

```bash
python main.py --listen 0.0.0.0 --path-prefix "/userendpoint/8MRWqVjZf0eomI"
```

now, open:

```bash
http://10.1.1.29:8188/userendpoint/8MRWqVjZf0eomI/
```

Can you add this feature？

### Existing Solutions

_No response_

### Other

_No response_