优化项目结构，修复部分问题

Utils/AppSetting.cs

@@ -1,11 +1,5 @@
 using Newtonsoft.Json.Linq;
-using System;
-using System.Collections.Generic;
-using System.Configuration;
 using System.IO;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
 
 namespace AntdUIDemo.Utils
 {

Utils/LoggerHelper.cs

@@ -1,9 +1,4 @@
 using NLog;
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
 
 namespace AntdUIDemo.Utils
 {

Utils/ThemeHelper.cs

@@ -1,11 +1,5 @@
-using System;
-using System.Collections.Generic;
+using Microsoft.Win32;
 using System.Drawing;
-using System.Linq;
-using System.Runtime.InteropServices;
-using System.Text;
-using System.Threading.Tasks;
-using Microsoft.Win32;
 
 namespace AntdUIDemo.Utils
 {