fix(contrib): 编译验证修正（Point internal / using Diagnostics）；补丁包标定 dotnet build 0w0e + 协议冒烟通过

contrib/windows-runner-actuate/native/NativeInput.cs

@@ -76,7 +76,7 @@ internal static class NativeInput
     private static extern uint SendInput(uint count, Input[] inputs, int size);
 
     [StructLayout(LayoutKind.Sequential)]
-    private struct Point { public int X; public int Y; }
+    internal struct Point { public int X; public int Y; }
 
     [StructLayout(LayoutKind.Sequential)]
     private struct Input