Request for complex XAML Islands sample combining WPF and WinUI controls in the same window

It would be great to have a more complex use case of XAML Islands with WPF and WinUI. For example, a sample where in the same window one could have WPF content like a Button, and then on the same window have some WinUI ListView.

The sample should demonstrate how to host both WPF and WinUI controls in the same window using XAML Islands. For instance, showing the code/setup for embedding WPF controls (like a Button) and WinUI controls (like ListView with WinUI Buttons) side-by-side .

If any supporting APIs or configuration changes are needed to make this integration work smoothly, those should be documented in the sample, for example create a HwndHost to host the islands on wpf.

Show how one can create xaml controls with templates in both wpf, or winui class library and how those are solved at runtime by the wpf app.

##Use Case

This sample would be useful for developers migrating or modernizing desktop applications, giving them a reference on how to leverage both legacy WPF controls and new WinUI controls in a single app window. It enables gradual modernization and feature enhancement of existing WPF apps using newer WinUI components.

Start with the WPF app and the HwndHost approach described in the issue, then identify how the sample can place a WPF Button beside a WinUI ListView containing WinUI Buttons. Done means a documented sample demonstrates both controls in one window, including template resolution for WPF and WinUI class libraries at runtime.