fix(lotto): _shared mount target 을 패키지 경로로 변경

마운트 `${RUNTIME_PATH}/_shared:/shared:ro` 가 컨테이너 안에서
`/shared/access_log.py` 만 노출하여 PYTHONPATH=/shared 에서 `from _shared.access_log import ...` 패키지 import 실패 (ModuleNotFoundError: No module named '_shared'). mount target 을 `/shared/_shared` 로 변경하여 `/shared/_shared/__init__.py` 가 패키지로 인식되게 함.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

docker-compose.yml

@@ -17,7 +17,7 @@ services:
       - PYTHONPATH=/app:/shared
     volumes:
       - ${RUNTIME_PATH}/data:/app/data
-      - ${RUNTIME_PATH}/_shared:/shared:ro
+      - ${RUNTIME_PATH}/_shared:/shared/_shared:ro
     logging:
       driver: "json-file"
       options: