fix(whip_attack): treure entity_manager_ duplicat (ja viu a Entity)

source/game/entities/concrete/whip_attack.hpp

@@ -152,7 +152,7 @@ class WhipAttack : public Attack {
     // del nostre `getFeetY()` per delegar el bucket d'y-sort al jugador.
     float owner_feet_y_{0.0F};
 
-    EntityManager* entity_manager_{nullptr};
+    // `entity_manager_` viu a Entity (protected): l'utilitzem d'allà.
     const std::vector<Player*>* players_{nullptr};
 
     DirSprite sprite_north_;