Refactor pet action management: rename PetAction to PetActionGather, update related models and services, and enhance resource gathering logic.

Models/Pet.cs

@@ -13,7 +13,8 @@ namespace pet_companion_api.Models
         public int Level { get; set; }
         public string UserId { get; set; }
         public bool IsDead { get; set; }
-        public PetAction PetAction { get; set; }
+
+        public PetActionGather PetAction { get; set; }
         public DateTime ActionSince { get; set; }
     }
 }