public List<TradeHistoryResponse> findTradeHistories(final Long memberId, final Long authId, final boolean isSeller) {
        Member member = findMember(authId);
        member.validateAuth(memberId);
        return tradeHistoryRepository.findHistories(memberId, isSeller);
    }
@Test
    void 거래_내역을_조회한다() {
        // given
        TradeHistory savedHistory = tradeHistoryRepository.save(
                new TradeHistory(
                        1L,
                        2L,
                        1L,
                        10000,
                        10,
                        List.of()
                )
        );

        Member saved = memberRepository.save(MemberFixture.일반_유저_생성());

        // when
        List<TradeHistoryResponse> buyerHistories = memberService.findTradeHistories(saved.getId(), saved.getId(), false);

        // then
        assertSoftly(softly -> {
            softly.assertThat(buyerHistories).hasSize(1);
            softly.assertThat(buyerHistories.get(0).buyerName()).isEqualTo("buyer");
        });
    }