track applets mouse click events differently

--the applets mouse click events are now tracked
for View::MouseSignals tracking mechanism. This
way no MouseArea is used overlaied over the applets
for the mouse click events. In that way the applets
are using their own built-in functionality for mouse
click events and at the same time for Latte is tracking
only the neutral areas for this meaning the applets external
margins in order to obey Fitt's Law

BUG: 406215