remove UI objects when a task is deleted

app/task/taskmanager.h

@@ -42,6 +42,33 @@ public:
    */
   TaskManager();
 
+  /**
+   * @brief TaskManager Destructor
+   *
+   * Ensures all Tasks are deleted
+   */
+  virtual ~TaskManager();
+
+  /**
+   * @brief Deleted copy constructor
+   */
+  TaskManager(const TaskManager& other) = delete;
+
+  /**
+   * @brief Deleted move constructor
+   */
+  TaskManager(TaskManager&& other) = delete;
+
+  /**
+   * @brief Deleted copy assignment
+   */
+  TaskManager& operator=(const TaskManager& other) = delete;
+
+  /**
+   * @brief Deleted move assignment
+   */
+  TaskManager& operator=(TaskManager&& other) = delete;
+
   /**
    * @brief Add a new Task
    *
@@ -56,6 +83,11 @@ public:
    */
   void AddTask(Task *t);
 
+  /**
+   * @brief Forcibly
+   */
+  void Clear();
+
 signals:
   /**
    * @brief Signal emitted when a Task is added by AddTask()