define ship roles via added modules and allow multiple weapons

src/lib/core/EntityAdmin.h

@@ -66,6 +66,10 @@ public:
 
     entt::entity spawnHqProxy(QVector2D position, float hp, float maxHp);
 
+    // Creates a bare entity for module child entities (weapons, salvage, repair).
+    // Caller is responsible for attaching all required components.
+    entt::entity createModuleEntity();
+
 private:
     entt::entity createEntity();