Support for dragging outside of parent Stack widget

[matthewrice345]

Is your feature request related to a problem? Please describe. Is there any way to support drag, resize, etc where the transform box is partially outside of the parent Stack widget? It appears that the TransformableBox returns a Positioned widget which means that a solution like defer_pointer wouldn't work. Wrapping the Positioned with anything other than a Stack can cause errors.

Describe the solution you'd like The ability to drag a TransformableBox when it is partially or completely outside of the parent Stack widget. Currently the Stack.hitText function will not recognize the gestures.

Describe alternatives you've considered I tried to fork the library (great library BTW) and use a builder to allow me from an app to wrap the direct child of the Positioned widget in TransformableBox with a DeferPointer. This creates some other errors with the widget being out of context.

Additional context I'm aware I can place restrictions on allowing the TransformableBox to be allowed to go outside the stack. For my use case it is important that it does and I'm just looking for any possible solution you may have in mind.

Thanks!