Participation Service 백엔드 개발 완료

주요 구현 사항:
- 이벤트 참여 등록 및 중복 검증 (Redis Cache + DB)
- 참여자 목록 조회 (필터링, 검색, 페이징)
- 당첨자 추첨 (Fisher-Yates Shuffle 알고리즘)
- Kafka 이벤트 발행 (ParticipantRegistered)
- Redis 캐싱으로 성능 최적화
- 전화번호 마스킹 (개인정보 보호)
- 전역 예외 처리 및 검증

기술 스택:
- Spring Boot 3.x + JPA
- MySQL (참여자, 추첨 로그)
- Redis (캐싱, 중복 검증)
- Kafka (이벤트 발행)

API 엔드포인트:
- POST /events/{eventId}/participate
- GET /events/{eventId}/participants
- GET /events/{eventId}/participants/search
- POST /events/{eventId}/draw-winners
- GET /events/{eventId}/winners

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

participation-service/src/main/resources/application.yml

@@ -0,0 +1,88 @@
+spring:
+  application:
+    name: participation-service
+
+  datasource:
+    url: jdbc:mysql://${DB_HOST:localhost}:${DB_PORT:3306}/${DB_NAME:participation_db}?useSSL=false&serverTimezone=UTC&characterEncoding=UTF-8
+    username: ${DB_USER:root}
+    password: ${DB_PASSWORD:password}
+    driver-class-name: com.mysql.cj.jdbc.Driver
+    hikari:
+      maximum-pool-size: ${DB_POOL_SIZE:10}
+      minimum-idle: ${DB_MIN_IDLE:5}
+      connection-timeout: ${DB_CONN_TIMEOUT:30000}
+      idle-timeout: ${DB_IDLE_TIMEOUT:600000}
+      max-lifetime: ${DB_MAX_LIFETIME:1800000}
+
+  jpa:
+    hibernate:
+      ddl-auto: ${JPA_DDL_AUTO:validate}
+    show-sql: ${JPA_SHOW_SQL:false}
+    properties:
+      hibernate:
+        format_sql: true
+        use_sql_comments: true
+        dialect: org.hibernate.dialect.MySQL8Dialect
+
+  # Redis Configuration
+  data:
+    redis:
+      host: ${REDIS_HOST:localhost}
+      port: ${REDIS_PORT:6379}
+      password: ${REDIS_PASSWORD:}
+      timeout: ${REDIS_TIMEOUT:3000}
+      lettuce:
+        pool:
+          max-active: ${REDIS_POOL_MAX_ACTIVE:8}
+          max-idle: ${REDIS_POOL_MAX_IDLE:8}
+          min-idle: ${REDIS_POOL_MIN_IDLE:2}
+          max-wait: ${REDIS_POOL_MAX_WAIT:3000}
+
+  # Kafka Configuration
+  kafka:
+    bootstrap-servers: ${KAFKA_BOOTSTRAP_SERVERS:localhost:9092}
+    producer:
+      key-serializer: org.apache.kafka.common.serialization.StringSerializer
+      value-serializer: org.springframework.kafka.support.serializer.JsonSerializer
+      acks: ${KAFKA_PRODUCER_ACKS:all}
+      retries: ${KAFKA_PRODUCER_RETRIES:3}
+      properties:
+        max.in.flight.requests.per.connection: 1
+        enable.idempotence: true
+    # Topic Names
+    topics:
+      participant-registered: participant-events
+
+server:
+  port: ${SERVER_PORT:8084}
+  servlet:
+    context-path: /
+  error:
+    include-message: always
+    include-binding-errors: always
+
+# Logging
+logging:
+  level:
+    root: ${LOG_LEVEL_ROOT:INFO}
+    com.kt.event.participation: ${LOG_LEVEL_APP:DEBUG}
+    org.springframework.data.redis: ${LOG_LEVEL_REDIS:INFO}
+    org.springframework.kafka: ${LOG_LEVEL_KAFKA:INFO}
+  pattern:
+    console: "%d{yyyy-MM-dd HH:mm:ss} [%thread] %-5level %logger{36} - %msg%n"
+    file: "%d{yyyy-MM-dd HH:mm:ss} [%thread] %-5level %logger{36} - %msg%n"
+  file:
+    name: ${LOG_FILE_PATH:./logs}/participation-service.log
+    max-size: ${LOG_FILE_MAX_SIZE:10MB}
+    max-history: ${LOG_FILE_MAX_HISTORY:30}
+
+# Application-specific Configuration
+app:
+  cache:
+    duplicate-check-ttl: ${CACHE_DUPLICATE_TTL:604800} # 7 days in seconds
+    participant-list-ttl: ${CACHE_PARTICIPANT_TTL:600} # 10 minutes in seconds
+  lottery:
+    algorithm: FISHER_YATES_SHUFFLE
+    visit-bonus-weight: ${LOTTERY_VISIT_BONUS:2.0} # 매장 방문 고객 가중치
+  security:
+    phone-mask-pattern: "***-****-***" # 전화번호 마스킹 패턴