- Rename JustRespawned to JustAppeared, which better matches its behavior anyway.
- Properly invoke JustAppeared for new (re-)spawns - fixes#20111.
- Fix Thaddius script to work with dynamic_spawning (mostly unrelated to the above) - Feugen/Stalagg should really be a summon group, but I don't have time to fix that right now.
- Fix default value for DynamicEscortNPC to match worldserver.conf.dist.
(cherry picked from commit 184c45cfe0)