Core/PacketIO: Fixed SMSG_UPDATE_OBJECT packets going missing for new items

Closes #16906

src/server/game/Entities/Object/Object.cpp

@@ -688,10 +688,7 @@ void Object::BuildValuesUpdate(uint8 updateType, ByteBuffer* data, Player* targe
 void Object::AddToObjectUpdateIfNeeded()
 {
     if (m_inWorld && !m_objectUpdated)
-    {
-        AddToObjectUpdate();
-        m_objectUpdated = true;
-    }
+        m_objectUpdated = AddToObjectUpdate();
 }
 
 void Object::ClearUpdateMask(bool remove)
@@ -2761,9 +2758,10 @@ void WorldObject::BuildUpdate(UpdateDataMapType& data_map)
     ClearUpdateMask(false);
 }
 
-void WorldObject::AddToObjectUpdate()
+bool WorldObject::AddToObjectUpdate()
 {
     GetMap()->AddUpdateObject(this);
+    return true;
 }
 
 void WorldObject::RemoveFromObjectUpdate()