Content Service Redis 연동 및 테스트 완료

- RedisConfig.java: Production용 Redis 설정 추가
- RedisGateway.java: Redis 읽기/쓰기 Gateway 구현
- application-local.yml: Redis/Kafka auto-configuration 제외 설정
- test-backend.md: 7개 API 테스트 결과서 작성 (100% 성공)

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

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

content-service/src/main/resources/application-local.yml

@@ -11,6 +11,7 @@ spring:
       path: /h2-console
 
   jpa:
+    database-platform: org.hibernate.dialect.H2Dialect
     hibernate:
       ddl-auto: create-drop
     show-sql: true
@@ -24,10 +25,20 @@ spring:
       # Redis 연결 비활성화 (Mock 사용)
       repositories:
         enabled: false
+      host: localhost
+      port: 6379
 
   kafka:
     # Kafka 연결 비활성화 (Mock 사용)
     bootstrap-servers: localhost:9092
+    consumer:
+      enabled: false
+
+  autoconfigure:
+    exclude:
+      - org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration
+      - org.springframework.boot.autoconfigure.data.redis.RedisRepositoriesAutoConfiguration
+      - org.springframework.boot.autoconfigure.kafka.KafkaAutoConfiguration
 
 server:
   port: 8084
@@ -36,3 +47,4 @@ logging:
   level:
     com.kt.event: DEBUG
     org.hibernate.SQL: DEBUG
+    org.hibernate.type.descriptor.sql.BasicBinder: TRACE