fix: #40 - System.InvalidOperationException in Query.Despawn (thanks very much, Grogian!)
changes: Archetypes no longer GC themselves when being migrated (e.g. when bulk-removing or -adding components).
use
World.GC()for now if you have large or many transient Archetypes (usually happens with relations where target entities are despawned, as it takes an astronomical amount of iterations before that specific archetype would ever contain entities again). Future releases will automaticallyGCin World Catchup or similar, but this first requires some additional attributes to avoid collecting overly eagerly and having to re-create many archetypes.