ButtonOrientation.vertical does not work with QtyStyle.classic

[BearAndBunny]

As the title says, it is not possible to have a vertical layout with QtyStyle.classic where plus button is on top, then the quantity value and on the bottom the minus button. ButtonOrientation.vertical only works with either btnOnRight or btnOnLeft. But then the buttons are on top of each other and the value is to the left or right.

[pmatatias]

current concept is using prefixIcon and suffixIcon from TextFormField.

i think its possible to implement vertical orientation + classic style , but using additional Column widget.
I will try to add this feature later. however, feel free to open PR if you want to work on this feature.