Hello.

I'd like to ask about some inefficiencies in the user inventory.

1. Item rewards should be called individually, not in bulk.
2. To find items based on their 'defId' within the inventory, a full search is required.

For itemCatalogs, which can only hold one item, we need to check if the item exists in the user's inventory before issuing the reward.
The problem is that it only supports itemId-based verification.

Furthermore, since there's no bulk-based reward payment system, rewards must be paid out individually. However, setting up approximately 100 to 200 items initially...

results in inefficient code.