refactor AI system

src/balancing/ArenaSimulation.h

@@ -22,6 +22,8 @@ class BuildingSystem;
 class CombatSystem;
 class DynamicBodySystem;
 class MovementIntentSystem;
+class RepairSystem;
+class SalvagerSystem;
 class ShipSystem;
 class ScrapSystem;
 
@@ -96,6 +98,8 @@ private:
     std::unique_ptr<DynamicBodySystem>    m_dynamicBodySystem;
     std::unique_ptr<CombatSystem>   m_combatSystem;
     std::unique_ptr<ScrapSystem>    m_scrapSystem;
+    std::unique_ptr<SalvagerSystem> m_salvagerSystem;
+    std::unique_ptr<RepairSystem>   m_repairSystem;
 
     entt::entity m_team1HqEntity;
     entt::entity m_team2HqEntity;