[cmdpal] Add setting "ignore hotkey when full screen" (#38923)

* init

* merge main

* merge main

---------

Co-authored-by: Yu Leng (from Dev Box) <yuleng@microsoft.com>

src/modules/cmdpal/Microsoft.CmdPal.UI/Helpers/WindowHelper.cs

@@ -0,0 +1,28 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Runtime.InteropServices;
+
+namespace Microsoft.CmdPal.UI.Helpers;
+
+internal sealed partial class WindowHelper
+{
+    public static bool IsWindowFullscreen()
+    {
+        UserNotificationState state;
+
+        // https://learn.microsoft.com/en-us/windows/win32/api/shellapi/ne-shellapi-query_user_notification_state
+        if (Marshal.GetExceptionForHR(NativeMethods.SHQueryUserNotificationState(out state)) == null)
+        {
+            if (state == UserNotificationState.QUNS_RUNNING_D3D_FULL_SCREEN ||
+                state == UserNotificationState.QUNS_BUSY ||
+                state == UserNotificationState.QUNS_PRESENTATION_MODE)
+            {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}