Revert "dock: use required properties in dock item delegate, fixes context injection on Qt 6.8 (#2926)"

This reverts commit b8e2ce1da8.

quickshell/Modules/Dock/DockApps.qml

@@ -479,8 +479,6 @@ Item {
 
                 delegate: Item {
                     id: delegateItem
-                    required property var modelData
-                    required property int index
 
                     property var dockButton: {
                         switch (itemData.type) {
@@ -601,7 +599,7 @@ Item {
                         height: delegateItem.height
                         actualIconSize: root.iconSize
                         dockApps: root
-                        index: delegateItem.index
+                        index: model.index
                     }
 
                     DockTrashButton {
@@ -626,7 +624,7 @@ Item {
                         appData: itemData
                         contextMenu: root.contextMenu
                         dockApps: root
-                        index: delegateItem.index
+                        index: model.index
                         parentDockScreen: root.dockScreen
                         showWindowTitle: itemData?.type === "window" || itemData?.type === "grouped"
                         windowTitle: {