fix(agent-assignment): 소속 크리에이터 조회 시각을 KST로 변환한다

src/main/kotlin/kr/co/vividnext/sodalive/admin/partner/agent/read/AdminAgentReadService.kt

@@ -56,9 +56,19 @@ class AdminAgentReadService(
     fun getAssignedCreators(agentId: Long, offset: Long, limit: Long): GetAdminAgentAssignedCreatorResponse {
         validateAgent(agentId)
         val now = LocalDateTime.now()
+        val items = queryRepository.getAssignedCreators(agentId = agentId, offset = offset, limit = limit, currentTime = now)
+            .map {
+                it.copy(
+                    assignedAt = it.assignedAt
+                        .atZone(ZoneId.of("UTC"))
+                        .withZoneSameInstant(kstZoneId)
+                        .toLocalDateTime()
+                )
+            }
+
         return GetAdminAgentAssignedCreatorResponse(
             totalCount = queryRepository.getAssignedCreatorTotalCount(agentId = agentId, currentTime = now),
-            items = queryRepository.getAssignedCreators(agentId = agentId, offset = offset, limit = limit, currentTime = now)
+            items = items
         )
     }