Menu left/right cursor transfer is unstable

[zoe-codez]

Issue

When the cursor moves from left column to right column, it can move unexpectedly around on the screen, and result in the list scrolling to the top of the screen

Changes

List position scrolling should be maintained while cursor is not in column

Create a reference to the value that was selected in the unused column. This reference can be used to maintain the scrolling position while not affecting existing workflows

Stable transfers

Cursor should transfer directly left / right between columns, without affecting scrolling.
The exception to this is when attempting to transfer into a whitespace gap, which should be resolved by moving up 1.