feat: ISSUE #I69IJI 自动关闭到托盘以防止下载和安装中断

添加托盘图标，主窗口关闭后仍然在后台运行；左键单机托盘图标显示主窗口

Log: 添加托盘图标；重构 MainWindow 构造函数，拆分 UI 初始化代码至单独函数；修改启动时窗口渐变动画初始化位置至 showEvent 中

src/widgets/base/basewidgetopacity.h

@@ -8,17 +8,17 @@ DWIDGET_USE_NAMESPACE
 class BaseWidgetOpacity : public DBlurEffectWidget
 {
     Q_OBJECT
+
 public:
     explicit BaseWidgetOpacity(QWidget *parent = nullptr);
 
-signals:
-
-public slots:
-
-    // QWidget interface
 protected:
-    bool closeWindowAnimation = false;
+    void showEvent(QShowEvent *event) override;
     void closeEvent(QCloseEvent *event) override;
+
+protected:
+    bool showWindowAnimation = false;
+    bool closeWindowAnimation = false;
 };
 
 #endif // BASEWIDGETOPACITY_H