Menu cannot be operated with the remote control #91

Reported on the AG-216: the menu does not react to any remote button (D-pad, OK, Back).

To check:

• Opening (OK) and moving between items (D-pad) in single view and in multi-view, with the builds after fix: Escape also closes a menu opened by touch #65 (the menu layout takes focus in touch mode), feat: 8 camera slots, multi-view up to 3x3 (#13) #64 (the slot row is now in a HorizontalScrollView) and feat: reserved UDP RTP cell: hint in the 9th cell and U in the menu #71/feat: adaptive multi-view decoding (full rate or key frames per cell) and D for the debug text (#85) #86 (U and D buttons).
• Whether focus lands on the slot row at all after the menu opens from the remote, and whether the HorizontalScrollView or the focusable layout swallows D-pad keys.
• That Back/Escape still close the menu.

Fix, and add a device check (input keyevent D-pad sequence) to the next test round.