fix(config): Clarify Redis usage and remove session configuration

- Add comment to Redis config: caching only (not for sessions)
- Change session.store-type from redis to none
- Remove session timeout (unnecessary for JWT stateless auth)

The application uses JWT-based stateless authentication where:
- SecurityConfig sets SessionCreationPolicy.STATELESS
- Redis is used only for refresh token storage and token blacklist
- No server-side session management required

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

Co-Authored-By: Claude <[email protected]>

Author: JIWONKIMS

src/main/resources/application-prod.yml

@@ -26,7 +26,7 @@ spring:
         initialize-schema: false
 
   data:
-    redis:
+    redis:  # 캐싱 전용 (세션 저장 안함 - JWT 기반 stateless 인증 사용)
       host: ${REDIS_HOST}
       port: ${REDIS_PORT}
       password: ${REDIS_PASSWORD:}
@@ -43,8 +43,7 @@ spring:
     requested-heartbeat: 30
 
   session:
-    store-type: redis
-    timeout: 30m
+    store-type: none  # JWT 기반 인증 사용 - 세션 불필요
 
 management:
   endpoints: