Window & app require two clicks to close

### Describe the bug

I wondered why I had to click twice on the windows "close" button for the window to close and my app to shut down. I was able to narrow it down to the code below. It looks like it's caused by a `x:Load="False"` element in my `NavigationView`

### Steps to reproduce the bug

Download and run this example project: [test.zip](https://github.com/user-attachments/files/20489165/test.zip)

It essentially just contains this in the `Window`:

```

```

### Expected behavior

App & Window closes on first click on the window close button

### Screenshots

_No response_

### NuGet package version

WinUI 3 - Windows App SDK 1.8 Experimental 1: 1.8.250515001-experimental2

### Windows version

Windows 11 (24H2): Build 26100

### Additional context

_No response_

Start by running the attached test.zip with Windows App SDK 1.8 Experimental 2 and reproduce the two-click close behavior. Inspect the Window, NavigationView, NavigationView.MenuItems, and the TextBlock using x:Load="False"; done means the app and window close on the first click while preserving the reported reproduction.

Written by the indexing model from the issue text.