[Fix] 광고 노출 집계와 게재 기간 판단을 KST로 고정

진입점에서 TimeZone.setDefault(Asia/Seoul)을 하고 있어 런타임 동작은 문제없었지만,
기본 시간대 설정에 기대면 일별 노출 버킷이 엉뚱한 시각에 갈릴 수 있다.
BattleVoteServiceImpl과 같은 방식으로 KST를 명시한다.

Author: Roy-wonji

src/main/java/com/swyp/picke/domain/ad/service/AdClickService.java

@@ -9,6 +9,7 @@
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 import java.time.LocalDateTime;
+import java.time.ZoneId;
 import java.util.HexFormat;
 import java.util.Optional;
 import lombok.RequiredArgsConstructor;
@@ -24,6 +25,9 @@ public class AdClickService {
 
     private static final int USER_AGENT_MAX_LENGTH = 500;
 
+    /** 게재 기간 판단은 KST 기준이다. 진입점의 기본 시간대 설정에 기대지 않는다. */
+    private static final ZoneId KST = ZoneId.of("Asia/Seoul");
+
     private final AdCreativeRepository adCreativeRepository;
     private final AdClickLogRepository adClickLogRepository;
     private final AffiliateLinkResolver affiliateLinkResolver;
@@ -34,7 +38,7 @@ public class AdClickService {
     @Transactional(readOnly = true)
     public Optional<AdClickTarget> resolveTarget(String code) {
         return adCreativeRepository.findByCode(code)
-                .filter(creative -> creative.isServable(LocalDateTime.now()))
+                .filter(creative -> creative.isServable(LocalDateTime.now(KST)))
                 .map(creative -> new AdClickTarget(
                         creative.getId(),
                         creative.getSlot(),

src/main/java/com/swyp/picke/domain/ad/service/AdQueryService.java

@@ -9,6 +9,7 @@
 import com.swyp.picke.domain.ad.repository.AdImpressionDailyRepository;
 import java.time.LocalDate;
 import java.time.LocalDateTime;
+import java.time.ZoneId;
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
@@ -25,6 +26,9 @@
 @RequiredArgsConstructor
 public class AdQueryService {
 
+    /** 노출 집계 버킷과 게재 기간은 KST 기준이다. 진입점의 기본 시간대 설정에 기대지 않는다. */
+    private static final ZoneId KST = ZoneId.of("Asia/Seoul");
+
     private final AdCreativeRepository adCreativeRepository;
     private final AdImpressionDailyRepository adImpressionDailyRepository;
 
@@ -37,7 +41,7 @@ public class AdQueryService {
      */
     @Transactional(readOnly = true)
     public List<AdResponse> findServableAds(AdSlotCode slot, int size) {
-        LocalDateTime now = LocalDateTime.now();
+        LocalDateTime now = LocalDateTime.now(KST);
 
         List<AdCreative> candidates = adCreativeRepository.findAllBySlotAndStatus(slot, AdStatus.ACTIVE).stream()
                 .filter(creative -> creative.isServable(now))
@@ -54,7 +58,7 @@ public List<AdResponse> findServableAds(AdSlotCode slot, int size) {
      */
     @Transactional(readOnly = true)
     public List<AdResponse> findLandingAds() {
-        LocalDateTime now = LocalDateTime.now();
+        LocalDateTime now = LocalDateTime.now(KST);
 
         return adCreativeRepository.findAllByStatusOrderByIdDesc(AdStatus.ACTIVE).stream()
                 .filter(creative -> creative.isServable(now))
@@ -68,7 +72,7 @@ public List<AdResponse> findLandingAds() {
      */
     @Transactional
     public void recordImpressions(List<String> codes) {
-        LocalDate today = LocalDate.now();
+        LocalDate today = LocalDate.now(KST);
 
         List<ImpressionTarget> targets = adCreativeRepository.findAllByCodeIn(codes).stream()
                 .map(creative -> new ImpressionTarget(creative.getId(), creative.getSlot()))