Key navigation fixes in player window input fields (fixes #3039, #3206)

[svobs]

• [x] I have read CONTRIBUTING.md
• [x] This implements/fixes issue #3039, #3206.

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Description:

1. Adds a check for arrow keys to text input fields, so that they always navigate inside the text instead of activating menu items.
2. Updates all the Quick Settings controls which should never have keyboard focus to refuse first responder status, so that pressing TAB or SHIFT+TAB in a text field doesn't create an unusable glowing focus ring around one of them.

[svobs]

Rebased + scaled down the changes so that only the text field issue is now addressed. The fix for table navigation was only halfway there anyway.

[svobs]

Rebased to fix merge problems + improved commit msg.

[uiryuu]

Thanks!