Relationship between ClipsToBounds and IsClippedToBounds

[davidbritch]

In MAUI.Controls, the value of ClipsToBounds is provided by the IsClippedToBounds property of Layout. For migration convenience from Xamarin.Forms, the IsClippedToBounds property defaults to false, so layouts in MAUI.Controls do not clip by default.

https://github.com/dotnet/maui/pull/16833

This should be mentioned in the migration docs, and potentially the layout docs. It may require additional content adding on how the layout engine works.