better ddcutil handling, revert to using onMoved brightness slider, fix osd region

Modules/Polkit/Polkit.qml

@@ -28,9 +28,7 @@ Scope {
 		visible: false
 
 		Connections {
-			target: root
-
-			onShouldShowChanged: {
+			function onShouldShowChanged(): void {
 				if (root.shouldShow) {
 					panelWindow.visible = true;
 					openAnim.start();
@@ -38,6 +36,8 @@ Scope {
 					closeAnim.start();
 				}
 			}
+
+			target: root
 		}
 
 		Anim {