ExtendsContentIntoTitleBar causes the crash of the app when closing in minimized state

### Describe the bug

The app will crash if you try to close it when minimized in the taskbar providing the following message:


NOTE: I'm not sure if this is more related to WinUI or WASDK.

### Steps to reproduce the bug

1. create a new app
2. copy the few example lines found in the official docs:
3. launch the app,
4. minimize it
5. right click on the icon is taskbar and close it.

### Expected behavior

_No response_

### Screenshots

_No response_

### NuGet package version

Windows App SDK 1.6.1: 1.6.240923002

### Packaging type

Packaged (MSIX)

### Windows version

Windows 10 version 22H2 (19045, 2022 Update)

### IDE

Visual Studio 2022

### Additional context

_No response_

Start by reproducing the crash using the documented SetTitleBar example on Windows 10 with Windows App SDK 1.6.1, then trace the minimized-window close path and the ExtendsContentIntoTitleBar behavior. Done means closing the minimized app from the taskbar no longer crashes.

Written by the indexing model from the issue text.