Items collection is of type IList instead of type object

[Balkoth]

The base control ListView has its ItemsSource of type object while the implementation here tries to be clever and introduce a new property hiding the base property of type IList?.

This makes it incredibly hard to replace, because its no longer a simple swap in the xaml, but everything touching the collection has to be redone. Escpecially when someone already has setup the ListView.ItemsSource from CommunityToolkit.WinUI.Collections.AdvancedCollectionView where collection changes and filtering are already handled and notified back to the UI.

[w-ahmad]

I agree, I am actually working on it make it working with ICollectionView and will keep here posted.

[w-ahmad]

the ItemsSource is now type of object in this PR #310 and it can now work wtih ICollectionView or AdvancedCollectionView.