Blazor hybrid desktop apps (.NET MAUI)

[guardrex]

• https://docs.microsoft.com/dotnet/maui/get-started/installation
• https://github.com/dotnet/aspnetcore/issues/27217
• https://devblogs.microsoft.com/aspnet/asp-net-core-updates-in-net-6-preview-3/#blazorwebview-controls-for-wpf-windows-forms
• https://devblogs.microsoft.com/aspnet/asp-net-core-updates-in-net-6-preview-4/#net-maui-blazor-apps
• .NET MAUI docs
• Microsoft .NET Blog (category: ".NET MAUI")

When we have content to link in this doc set, update the release notes to point to it (and we'll 🔪 the .NET Blog entry) ...

https://docs.microsoft.com/en-us/aspnet/core/release-notes/aspnetcore-6.0