feat(wip): 경매 세부 기능 구현

hwe/sammo/DTO/AuctionBidItem.php

@@ -2,9 +2,11 @@
 
 namespace sammo\DTO;
 
+use sammo\DTO\Attr\Convert;
 use sammo\DTO\Attr\JsonString;
 use sammo\DTO\Attr\NullIsUndefined;
 use sammo\DTO\Attr\RawName;
+use sammo\DTO\Converter\DateTimeConverter;
 
 class AuctionBidItem extends DTO
 {
@@ -20,7 +22,8 @@ class AuctionBidItem extends DTO
 
     public int $amount,
 
-    public string $date,
+    #[Convert(DateTimeConverter::class)]
+    public \DateTimeImmutable $date,
     #[JsonString]
     public AuctionBidItemData $data,
   ) {