The mouse scroll wheel was not working in the creative inventory at
all. UIController remaps wheel input from OTHER_STICK to UP/DOWN for
KBM users, but the base container menu handler consumed UP/DOWN for
grid navigation before it could reach the creative menu's page
scrolling logic in handleAdditionalKeyPress. Fixed by detecting
scroll wheel input on UP/DOWN in the base handler and forwarding it
as OTHER_STICK to handleAdditionalKeyPress instead.
Also fixed the controller right stick scrolling way too fast: it was
jumping TabSpec::rows (5) rows per tick at 100ms repeat rate, which
blew through the entire item list almost instantly. Reduced to 1 row
per tick so scrolling feels controlled on both input methods.
cb2b532f70