Cannot authenticate using Entra ID in a partial trust application

### Describe the bug

So I've spent two days on this now - I cannot find a working example of a partial trust application authenticating with Entra ID

WebAuthenticationBroker (https://github.com/microsoft/Windows-universal-samples/blob/main/Samples/WebAuthenticationBroker/cs/Scenario2_Twitter.xaml.cs) doesn't work with a meaningless error (UserCancelled)

MSAL doesn't work https://github.com/microsoft/microsoft-ui-xaml/issues/10657

WebView2 doesnt working either, its always just a blank white page

This must be one of, if not the most common scenario for security conscious organizations (for whom partial trust applications were created for surely?)

So does the feature really not work? I have to use full trust to authentication Microsoft's own IDP?

### Steps to reproduce the bug

Do anything

### Expected behavior

_No response_

### Screenshots

_No response_

### NuGet package version

None

### Windows version

_No response_

### Additional context

_No response_

The report names WebAuthenticationBroker's Scenario2_Twitter.xaml.cs, MSAL, WebView2, and microsoft-ui-xaml issue #10657, but provides no repository file or reproducible steps. Begin by testing each named authentication path in a partial-trust application; done means a working Entra ID flow or actionable evidence of a framework limitation.

Written by the indexing model from the issue text.