Keyboard focus enhancement

[MassiminoilTrace]

Hi, thanks for your app.
I'm writing this issue to note down a possible enhancement.

I was trying the Headcalculation game, and each time I submit a result, the keyboard loses its focus.
So, each time the user has to move the finger back to the top of the screen, open the keyboard, go back in the middle, enter the number, go back down, confirm, repeat.

Two possible ways to fix it come to my mind:

• forcing the focus on the text input component. I don't know how flutter focus system works, so I don't know if the keyboard would be kept opened, or if the keyboard would be hidden and shown again at each step.
• add buttons to make a "fake onscreen keyboard", which will remain always drawn, instead of using the system keyboard. As only digits are needed, it may be a solution.

[fkropfhamer]

Thanks for the feedback! I am not a big fan of the system keyboard. I will try to replace it with my own implementation!