A: 添加任务栏窗口界面 (TaskbarWindow.xaml) 以显示实时网络流量；新增工具类 TaskbarHelper 获取任务栏位置

A: README 更新，详述功能清单及说明
A: 添加图片资源(img.png, img_1.png, img_2.png, img_3.png)
D: 移除 MainWindow.xaml.cs 中无用引用

Shell/Utils/TaskbarHelper.cs

@@ -0,0 +1,35 @@
+namespace Shell.Utils;
+
+using System;
+using System.Runtime.InteropServices;
+
+public static class TaskbarHelper
+{
+    [DllImport("shell32.dll", SetLastError = true)]
+    static extern UInt32 SHAppBarMessage(UInt32 dwMessage, ref APPBARDATA pData);
+
+    [StructLayout(LayoutKind.Sequential)]
+    public struct APPBARDATA
+    {
+        public UInt32 cbSize;
+        public IntPtr hWnd;
+        public UInt32 uCallbackMessage;
+        public UInt32 uEdge;
+        public RECT rc;
+        public Int32 lParam;
+    }
+
+    [StructLayout(LayoutKind.Sequential)]
+    public struct RECT
+    {
+        public int left, top, right, bottom;
+    }
+
+    public static RECT GetTaskbarPosition()
+    {
+        APPBARDATA data = new APPBARDATA();
+        data.cbSize = (UInt32)Marshal.SizeOf(typeof(APPBARDATA));
+        SHAppBarMessage(0x00000005, ref data); // ABM_GETTASKBARPOS
+        return data.rc;
+    }
+}