Widgets: Add window state handler

Sine Striker

2023-12-11 677e7a737897e8c2a60564085821545810369e02

 src/core/contexts/abstractwindowcontext_p.h

@@ -48,6 +48,7 @@
            ShowSystemMenuHook,
            NeedsDrawBordersHook,
            DrawBordersHook,
            QueryBorderThicknessHook
        };
        virtual void virtual_hook(int id, void *data);