settings: scroll the sidebar with the keyboard highlight

fixes #3175

quickshell/Modals/Settings/SettingsSidebar.qml

@@ -55,6 +55,16 @@ Rectangle {
         autoExpandForTab(keyboardHighlightIndex);
     }
 
+    function ensureRowVisible(item) {
+        if (!item || sidebarFlickable.height <= 0)
+            return;
+        const itemY = item.mapToItem(sidebarFlickable.contentItem, 0, 0).y;
+        const viewH = sidebarFlickable.height;
+        if (itemY >= sidebarFlickable.contentY && itemY + item.height <= sidebarFlickable.contentY + viewH)
+            return;
+        sidebarFlickable.contentY = Math.max(0, Math.min(itemY - viewH / 4, sidebarFlickable.contentHeight - viewH));
+    }
+
     function selectHighlighted() {
         if (keyboardHighlightIndex < 0)
             return;
@@ -723,6 +733,7 @@ Rectangle {
     }
 
     DankFlickable {
+        id: sidebarFlickable
         anchors.fill: parent
         clip: true
         contentHeight: sidebarColumn.height
@@ -974,6 +985,10 @@ Rectangle {
                         readonly property bool hasTab: categoryDelegate.modelData.tabIndex !== undefined && !categoryDelegate.modelData.children
                         readonly property bool isActive: hasTab && root.currentIndex === categoryDelegate.modelData.tabIndex
                         readonly property bool isHighlighted: hasTab && root.keyboardHighlightIndex === categoryDelegate.modelData.tabIndex
+                        onIsHighlightedChanged: {
+                            if (isHighlighted)
+                                Qt.callLater(root.ensureRowVisible, categoryRow);
+                        }
 
                         color: {
                             if (isActive)
@@ -1069,6 +1084,10 @@ Rectangle {
 
                                 readonly property bool isActive: root.currentIndex === modelData.tabIndex
                                 readonly property bool isHighlighted: root.keyboardHighlightIndex === modelData.tabIndex
+                                onIsHighlightedChanged: {
+                                    if (isHighlighted)
+                                        Qt.callLater(root.ensureRowVisible, childDelegate);
+                                }
 
                                 width: childrenColumn.width
                                 height: Math.max(Theme.iconSize - 4, Theme.fontSizeSmall + 1) + Theme.spacingS * 2