add rigidbody:is_selectable, :set_selectable

src/physics/Hitbox.hpp

@@ -65,6 +65,7 @@ struct Hitbox {
     float stepHeight = 0.5f;
     float mass = 1.0f;
     float elasticity = 0.0f;
+    bool selectable = true;
     std::string material;
     std::string groundMaterial;
     glm::vec3 groundVelocity {};