Experience optimization

Optimization: Added merchant portraits.
Bug Fix: Main quests were not spawning enemies due to terrain restrictions.
Bug Fix: After exploring a secret realm, character traits were lost.
Optimization: Veterinary medicine is no longer available for aging animals in the pasture to prevent waste.
Bug Fix: Dropped items were rapidly disappearing after anthill migration.
Optimization: On the minimap, the color of the Adamantine Mountains has been changed to dark red to distinguish it from the monsters.