if entity was despawned such as in a hierachy

Objective

• DespawnOnExit / DespawnOnEnter logs errors with despawning.
  Most if not all use cases don't care if the item is already despawned.
  The user is typically saying "Ensure it is despawned" rather then "You should be the one to despawn"
• Fixes DespawnOnExit / DespawnOnEnter causes log spam when despawning hierarchies #21832

Solution

• Changes the state_scoped code to use try despawn

Testing

• I updated example state_scoped to include children with DespawnOnExit/DespawnOnEnter and added a brief explanation then I ran the examples