[Feature Request]: Make dynamic widgets first class as inputs are

### Is there an existing issue for this?

- [x] I have searched the existing issues and checked the recent builds/commits

### What would your feature do ?

Adding dynamically a new input with `addInput` is easy. At least when you are happy that it's located at the end.

But when dynamically adding a widget with `addWidget()` it doesn't have full functionality as Comfy widgets have. It is missing the additional input. To add it you must manually add a input at the same time as `#addInputWidget` is not exposed.

### Proposed workflow

1. Have code, e.g. in a custom `onConnectionsChange` that wants to create additional dynamically inputs and widgets.
2. Add a widget
3. Wonder that you can't connect a link to it.

### Additional information

_No response_

┆Issue is synchronized with this [Notion page](https://www.notion.so/Issue-3956-Feature-Request-Make-dynamic-widgets-first-class-as-inputs-are-1fa6d73d365081318491dd4c0f21860c) by [Unito](https://www.unito.io)