fix: 统一使用 /opt/camtalk/.env 路径，act_runner 挂载宿主机目录后直接读取

docker-compose.yml

@@ -18,7 +18,7 @@ services:
       dockerfile: Dockerfile
     container_name: camtalk-backend
     env_file:
-      - /root/camtalk/.env
+      - /opt/camtalk/.env
     environment:
       # 三级存储配置（敏感信息通过 env_file 注入）
       - CAMTALK_STORAGE_REDIS_ENABLED=${CAMTALK_STORAGE_REDIS_ENABLED:-true}
@@ -38,7 +38,7 @@ services:
     image: docker.m.daocloud.io/library/postgres:15-alpine
     container_name: camtalk-postgres
     env_file:
-      - /root/camtalk/.env
+      - /opt/camtalk/.env
     environment:
       POSTGRES_DB: camtalk
     volumes:
@@ -57,7 +57,7 @@ services:
     image: docker.m.daocloud.io/library/redis:7-alpine
     container_name: camtalk-redis
     env_file:
-      - /root/camtalk/.env
+      - /opt/camtalk/.env
     command: >
       sh -c '
       if [ -n "$$CAMTALK_REDIS_PASSWORD" ]; then