mage global menu screen aware

Summary:
--a new screenGeometry property is added in the
AppMenuModel in order to be used for filtering
windows based on their geometry.

BUG: 384895, 395853

Test Plan:
--validate that when moving a window between different screens the global menu applet is updated accordingly
--checkout that nothing has broke because of this new behavior

Reviewers: #plasma, broulik, davidedmundson

Reviewed By: #plasma, davidedmundson

Subscribers: mart, davidedmundson, plasma-devel

Tags: #plasma

Differential Revision: https://phabricator.kde.org/D16768