@Observable currently fails when the class has lazy properties.
This seems to be because @ObservationTracked turns it into a computed property, but the lazy attribute is still preserved.
Since lazy computed properties are invalid, this results in the error:
'lazy' cannot be used on a computed property
This feels like an oversight to me. @ObservationTracked should be able to remove lazy from the computed property, while preserving it for the @ObservationUntracked backing copy.
I manually recreated this special handling of lazy and it appears to work as expected: