fix(deck-picker): prefer to use binding over checking 'fragmented' status

[david-allison]

Now we have moved to bindings, we can more easily detect whether the screen is fragmented

• chore: convert DeckPicker to ViewBinding #19420

Fixes

• ⚠️ I suspect this fixes [BUG] DeckPicker/Tablet: onResume Required value was null #19555

Approach

• use tryShowStudyOptionsPanel to detect if the view is fragmented
• and a few logical improvements based on a view being nullable

How Has This Been Tested?

⚠️ API 34 tablet emulator - screen still works, unit tests still run

Learning (optional, can help others)

I strongly suspect this is another android:configChanges bug:

• Do not handle configuration changes manually #12832

Checklist

• You have a descriptive commit message with a short title (first line, max 50 chars).
• You have commented your code, particularly in hard-to-understand areas
• You have performed a self-review of your own code
• UI changes: include screenshots of all affected screens (in particular showing any new or changed strings)
• UI Changes: You have tested your change using the Google Accessibility Scanner

[mikehardy]

all seems reasonable