docs(gift): 선물함 리스트 계약 필드를 기록한다

docs/20260929_크리에이터_선물하기/client-api-summary.md

@@ -145,6 +145,12 @@ data class GiftListItemResponse(
     val priceCan: Int,
     val categoryName: String,
     val sizeName: String,
+    val counterpartMemberId: Long,
+    val counterpartNickname: String,
+    val counterpartProfileImageUrl: String,
+    val recipientAddressRegistered: Boolean,
+    val recipientAddressDeadlineAt: String?,
+    val canceledAt: String?,
     val createdAt: String?
 )