fix: admin 审批链路查询条件缺失与网关路由缺失

SearchUserVerifications 查询条件硬编码了 user_id=0 导致 admin 查询
始终返回空列表，改为条件构建模式。envoy 缺少 /api/v1/admin 前缀
路由导致审批接口 404。新增 users-rpc 启动时从环境变量自动初始化
管理员账户。

deploy/dev/docker-compose.yml

@@ -118,6 +118,10 @@ services:
     container_name: juwan-user-rpc
     restart: unless-stopped
     env_file: .env
+    environment:
+      ADMIN_USERNAME: ${ADMIN_USERNAME}
+      ADMIN_PASSWORD: ${ADMIN_PASSWORD}
+      ADMIN_EMAIL: ${ADMIN_EMAIL}
     depends_on:
       postgres:
         condition: service_healthy