refactor AI system

src/lib/ecs/component/AttackBehavior.h

@@ -0,0 +1,13 @@
+#pragma once
+
+#include <optional>
+
+#include "entt/entity/entity.hpp"
+
+// Combat behavior for ships with weapons (was ThreatResponseBehaviorComponent).
+// The evaluator sets currentTarget; the executor pushes it to in-range weapons.
+struct AttackBehavior
+{
+    std::optional<entt::entity> currentTarget;
+    float                       score = 0.0f;
+};