refactor: 결제 취소시 CanceledPaymentEntity를 반환하도록 수정

src/main/kotlin/roomescape/payment/business/PaymentWriter.kt

@@ -68,20 +68,18 @@ class PaymentWriter(
         payment: PaymentEntity,
         requestedAt: LocalDateTime,
         cancelResponse: PaymentClientCancelResponse
-    ) {
+    ): CanceledPaymentEntity {
         log.debug { "[PaymentWriterV2.cancelPayment] 결제 취소 정보 저장 시작: payment.id=${payment.id}" }
 
-        val canceledPayment: CanceledPaymentEntity = cancelResponse.cancels.toEntity(
+        paymentRepository.save(payment.apply { this.cancel() })
+
+        return cancelResponse.cancels.toEntity(
             id = tsidFactory.next(),
             paymentId = payment.id,
             cancelRequestedAt = requestedAt,
             canceledBy = memberId
-        )
-
-        run {
-            canceledPaymentRepository.save(canceledPayment)
-            paymentRepository.save(payment.apply { this.cancel() })
-        }.also {
+        ).also {
+            canceledPaymentRepository.save(it)
             log.debug { "[PaymentWriterV2.cancelPayment] 결제 취소 정보 저장 완료: payment.id=${payment.id}" }
         }
     }