Moving points should not be overrided by disambiguation menu, so we
track where the disambiguation event started and only trigger the menu
if the mouse hasn't moved a full unit in x/y
Fixes https://gitlab.com/kicad/code/kicad/issues/9132
Previously, we were checking if the selection tool was the top of the
stack but this ignored many other "secondary" tools that might be
running such as the point editor. These still allow the selection tool
to handle events such as clicks. This change allows the selection tool
to handle clicks when it is the primary tool on the stack rather than
the top
Fixes https://gitlab.com/kicad/code/kicad/issues/9110
This standardizes selection tools in SELECTION_TOOL class to be able to
handle a long-click as asking for a non-heuristic disambiguation menu.
Fixes https://gitlab.com/kicad/code/kicad/issues/8490
Seth Hillbrand
Jeff Young