pdInput: disable TAB key handling

I'm starting to rethink my approach to key hooking, as it's introducing
a number of complex interactions that are very hard to handle properly.

In the meantime, I'm disabling pdInput's TAB key tracking capabilities,
because it's extremely difficult to apply custom tab handling with VB
constantly doing its own focus management in the background.
Button Strip UC: allow arrow keys for changing active button

Right/Left to navigate buttons, space bar to activate