feat: set focus to first expanded notification item

1. Add logic to automatically set ListView currentIndex to the first
notification item when expanding an app group
2. This improves keyboard navigation by moving focus to the newly
expanded content
3. Calculate the correct index by adding 1 to the expanded app index
4. Only apply the focus change when the root view is available

feat: 设置焦点到新展开的首条通知项

1. 添加逻辑在展开应用组时自动将 ListView 当前索引设置到第一条通知项
2. 通过将焦点移动到新展开的内容来改进键盘导航体验
3. 通过展开应用索引加1计算正确的索引位置
4. 仅在根视图可用时应用焦点更改
5.修复了删除后，焦点给到下一项
PMS: BUG-284987

Author: wjyrich

panels/notification/center/NotifyViewDelegate.qml

@@ -102,11 +102,21 @@ DelegateChooser {
             }
             onRemove: function () {
                 console.log("remove normal", model.id)
+                let removeIndex = index
                 notifyModel.remove(model.id)
+                let nextIndex = Math.min(removeIndex, root.view.count - 1)
+                if (nextIndex >= 0 && root.view.count > 0) {
+                    root.view.currentIndex = nextIndex
+                }
             }
             onDismiss: function () {
                 console.log("dismiss normal", model.id)
+                let dismissIndex = index
                 notifyModel.remove(model.id)
+                let nextIndex = Math.min(dismissIndex, root.view.count - 1)
+                if (nextIndex >= 0 && root.view.count > 0) {
+                    root.view.currentIndex = nextIndex
+                }
             }
             onActionInvoked: function (actionId) {
                 console.log("action normal", model.id, actionId)
@@ -163,7 +173,13 @@ DelegateChooser {
             onExpand: function ()
             {
                 console.log("expand")
-                notifyModel.expandApp(model.index)
+                let expandIndex = model.index
+                notifyModel.expandApp(expandIndex)
+                // 设置ListView的currentIndex到新展开的首条通知项 (将焦点设置到新展开的通知的第一项)
+                if (root.view) {
+                    let firstExpandedIndex = expandIndex + 1
+                    root.view.currentIndex = firstExpandedIndex
+                }
             }
             onSetting: function (pos) {
                 let tmp = mapToItem(root.view, pos)