Adding a remove_nil_items? constraint should be pretty straightforward.
But now that you mention it, it’s also unexcepted behavior that nil values make it through to the database if they are initially empty strings.
To circumvent that issue, I guess the is_nil check would benefit from being rerun after applying the item’s type constraints here:
https://github.com/ash-project/ash/blob/v2.21.14/lib/ash/type/type.ex#L704-L713
But that would probably be considered a breaking change, right?
Maybe we should continue that discussion in a GitHub issue or draft PR, let me know!
