feat: add show item on system tray (#533)

ui/flutter/lib/i18n/langs/en_us.dart

@@ -60,6 +60,7 @@ const enUS = {
     'set': 'SET',
     'portInUse': 'Port [@port] is in use, please change the port',
     'effectAfterRestart': 'Effect after restart',
+    'show': 'Show',
     'startAll': 'Start All',
     'pauseAll': 'Pause All',
     'deleteTask': 'Delete Task',

ui/flutter/lib/i18n/langs/zh_cn.dart

@@ -58,6 +58,7 @@ const zhCN = {
     'set': '已设置',
     'portInUse': '端口[@port]已被占用，请更换端口',
     'effectAfterRestart': '此配置项将在重启应用后生效',
+    'show': '显示',
     'startAll': '全部开始',
     'pauseAll': '全部暂停',
     'deleteTask': '删除任务',

ui/flutter/lib/i18n/langs/zh_tw.dart

@@ -58,6 +58,7 @@ const zhTW = {
     'set': '已設定',
     'portInUse': '端口[@port]已被占用，請更換端口',
     'effectAfterRestart': '重啟後生效',
+    'show': '顯示',
     'startAll': '全部開始',
     'pauseAll': '全部暫停',
     'deleteTask': '刪除任務',