feat: add taskbar click handler for locked state

1. Implement handleDragAreaClick function to activate applications when
taskbar is locked
2. Add coordinate mapping logic to convert drag area clicks to app
container positions
3. Support all dock positions (bottom, top, left, right) with
appropriate coordinate adjustments
4. Connect click handler to drag area onClicked event when Panel.locked
is true
5. Expose appContainer property in TaskManager for external access

feat: 为锁定状态添加任务栏点击处理功能

1. 实现 handleDragAreaClick 函数，在任务栏锁定时激活应用程序
2. 添加坐标映射逻辑，将拖拽区域点击转换为应用容器位置
3. 支持所有停靠位置（底部、顶部、左侧、右侧）并相应调整坐标
4. 当 Panel.locked 为 true 时，将点击处理程序连接到拖拽区域的 onClicked
事件
5. 在 TaskManager 中暴露 appContainer 属性以供外部访问

PMS: TASK-383127

Author: wjyrich

panels/dock/package/main.qml

@@ -263,6 +263,49 @@ Window {
         dockRightPartModel.update()
     }
 
+    // 在任务栏锁定状态下，点击任务栏相应位置的应用
+    function handleDragAreaClick(x, y) {
+        if (!Panel.locked) return false
+        
+        let taskmanager = DS.applet("org.deepin.ds.dock.taskmanager")
+        if (!taskmanager || !taskmanager.rootObject) return false
+        
+        let dataModel = taskmanager.dataModel
+        if (!dataModel) return false
+        
+        let appContainer = taskmanager.rootObject.appContainer
+        if (!appContainer) return false
+        
+        // 将dragArea的点击坐标映射到应用容器
+        let dragAreaPos = dragArea.mapToItem(appContainer, x, y)
+        
+        // 根据dock位置调整坐标映射逻辑
+        let targetPos = Qt.point(0, 0)
+        if (Panel.position === Dock.Bottom) {
+            targetPos.x = dragAreaPos.x
+            targetPos.y = appContainer.height / 2
+        } else if (Panel.position === Dock.Top) {
+            targetPos.x = dragAreaPos.x  
+            targetPos.y = appContainer.height / 2
+        } else if (Panel.position === Dock.Left) {
+            targetPos.x = appContainer.width / 2
+            targetPos.y = dragAreaPos.y
+        } else if (Panel.position === Dock.Right) {
+            targetPos.x = appContainer.width / 2
+            targetPos.y = dragAreaPos.y
+        }
+        
+        // 计算点击的应用索引
+        let clickedIndex = appContainer.indexAt(targetPos.x, targetPos.y)
+        
+        if (clickedIndex >= 0 && clickedIndex < dataModel.rowCount()) {
+            let modelIndex = dataModel.index(clickedIndex, 0)
+            taskmanager.requestActivate(modelIndex)
+            return true
+        }
+        return false
+    }
+
     Loader {
         id: dockMenuLoader
         active: false
@@ -561,7 +604,12 @@ Window {
         }
 
         // this used for blocking MouseEvent sent to bottom MouseArea
-        onClicked: {}
+        onClicked: function(mouse) {
+            // 在锁定状态下，点击dragArea启动相应位置的应用
+            if (Panel.locked) {
+                handleDragAreaClick(mouse.x, mouse.y)
+            }
+        }
 
         onPositionChanged: function(mouse) {
             if (Panel.locked || !dock.isDragging) return

panels/dock/taskmanager/package/TaskManager.qml

@@ -15,6 +15,7 @@ ContainmentItem {
     property int dockOrder: 16
     property int remainingSpacesForTaskManager: Panel.itemAlignment === Dock.LeftAlignment ? Panel.rootObject.dockLeftSpaceForCenter : Panel.rootObject.dockRemainingSpaceForCenter
     property int forceRelayoutWorkaround: 0
+    property alias appContainer: appContainer
 
     // 用于居中计算的实际应用区域尺寸
     property int appContainerWidth: useColumnLayout ? Panel.rootObject.dockSize : (appContainer.implicitWidth + forceRelayoutWorkaround)