Add exit function to the main interface for Desktop

v2rayN/ServiceLib/Resx/ResUI.Designer.cs

@@ -870,6 +870,15 @@ namespace ServiceLib.Resx {
             }
         }
         
+        /// <summary>
+        ///   查找类似 Are you sure to exit? 的本地化字符串。
+        /// </summary>
+        public static string menuExitTips {
+            get {
+                return ResourceManager.GetString("menuExitTips", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   查找类似 Export selected server for complete configuration 的本地化字符串。
         /// </summary>

v2rayN/ServiceLib/Resx/ResUI.resx

@@ -1363,4 +1363,7 @@
   <data name="TbSettingsCurrentFontFamilyLinuxTip" xml:space="preserve">
     <value>Install the font to the system and restart the settings</value>
   </data>
+  <data name="menuExitTips" xml:space="preserve">
+    <value>Are you sure to exit?</value>
+  </data>
 </root>

v2rayN/ServiceLib/Resx/ResUI.zh-Hans.resx

@@ -1360,4 +1360,7 @@
   <data name="TbSettingsCurrentFontFamilyLinuxTip" xml:space="preserve">
     <value>安装字体到系统中，重启设置</value>
   </data>
+  <data name="menuExitTips" xml:space="preserve">
+    <value>是否确定退出？</value>
+  </data>
 </root>

v2rayN/ServiceLib/Resx/ResUI.zh-Hant.resx

@@ -1240,4 +1240,7 @@
   <data name="TbSettingsCurrentFontFamilyLinuxTip" xml:space="preserve">
     <value>安裝字體到系統中，重新啟動設定</value>
   </data>
+  <data name="menuExitTips" xml:space="preserve">
+    <value>是否確定退出？</value>
+  </data>
 </root>

v2rayN/ServiceLib/ViewModels/MainWindowViewModel.cs

@@ -52,6 +52,8 @@ namespace ServiceLib.ViewModels
 
         public ReactiveCommand<Unit, Unit> ReloadCmd { get; }
 
+        public ReactiveCommand<Unit, Unit> ExitCmd { get; }
+
         [Reactive]
         public bool BlReloadEnabled { get; set; }
 
@@ -187,6 +189,11 @@ namespace ServiceLib.ViewModels
                 await Reload();
             });
 
+            ExitCmd = ReactiveCommand.CreateFromTask(async () =>
+            {
+                await Exit();
+            });
+
             RegionalPresetDefaultCmd = ReactiveCommand.CreateFromTask(async () =>
             {
                 await ApplyRegionalPreset(EPresetType.Default);
@@ -588,6 +595,16 @@ namespace ServiceLib.ViewModels
             }
         }
 
+        private async Task Exit()
+        {
+            if (await _updateView?.Invoke(EViewAction.ShowYesNo, null) == false)
+            {
+                return;
+            }
+
+            await MyAppExitAsync(false);
+        }
+
         #endregion core job
 
         #region Presets