make stations not attack other stations

src/lib/sim/CombatSystem.h

@@ -45,12 +45,10 @@ private:
                               std::vector<FireEvent>& out);
 
     // Find the nearest valid target for a defence station within its range.
-    // Enemy stations target player ships + HQ + PlayerDefenceStation.
-    // Player stations target enemy ships only.
+    // Both enemy and player stations target ships of the opposing faction only.
     std::optional<EntityId> acquireStationTarget(
         const Building& station, bool stationIsEnemy,
-        const ShipSystem& ships,
-        const BuildingSystem& buildings) const;
+        const ShipSystem& ships) const;
 
     // Return the world position of the entity, or nullopt if it no longer exists.
     std::optional<QVector2D> targetPosition(EntityId id,