feat: add tray icon to status bar

Signed-off-by: Kingtous <kingtous@qq.com>

flutter/lib/utils/tray_manager.dart

@@ -0,0 +1,22 @@
+import 'dart:io';
+
+import 'package:flutter_hbb/models/model.dart';
+import 'package:tray_manager/tray_manager.dart';
+
+Future<void> initTray({List<MenuItem>? extra_item}) async {
+  List<MenuItem> items = [
+    MenuItem(key: "show", label: translate("show rustdesk")),
+    MenuItem.separator(),
+    MenuItem(key: "quit", label: translate("quit rustdesk")),
+  ];
+  if (extra_item != null) {
+    items.insertAll(0, extra_item);
+  }
+  await Future.wait([
+    trayManager
+        .setIcon(Platform.isWindows ? "assets/logo.ico" : "assets/logo.png"),
+    trayManager.setContextMenu(Menu(items: items)),
+    trayManager.setToolTip("rustdesk"),
+    trayManager.setTitle("rustdesk")
+  ]);
+}