qs: large sweep of dead code removals

quickshell/Modules/Plugins/SliderSetting.qml

@@ -1,6 +1,7 @@
 import QtQuick
 import qs.Common
 import qs.Widgets
+import "../../Common/QmlUtils.js" as QmlUtils
 
 Column {
     id: root
@@ -20,7 +21,7 @@ Column {
     spacing: Theme.spacingS
 
     function loadValue() {
-        const settings = findSettings();
+        const settings = QmlUtils.findSettings(root.parent);
         if (settings && settings.pluginService) {
             value = settings.loadValue(settingKey, defaultValue);
         }
@@ -31,23 +32,12 @@ Column {
     }
 
     onValueChanged: {
-        const settings = findSettings();
+        const settings = QmlUtils.findSettings(root.parent);
         if (settings) {
             settings.saveValue(settingKey, value);
         }
     }
 
-    function findSettings() {
-        let item = parent;
-        while (item) {
-            if (item.saveValue !== undefined && item.loadValue !== undefined) {
-                return item;
-            }
-            item = item.parent;
-        }
-        return null;
-    }
-
     StyledText {
         text: root.label
         font.pixelSize: Theme.fontSizeMedium