有个想法，存储层是不是可以新增一个对密码解密的接口

## Why you need it?
Is your feature request related to a problem? Please describe in details
有这样一个需求，有公司要求数据库的密码不能明文放在配置文件里，是否可以增加一个接口，由用户自己去实现对db的username,password或者redis的mastername,host,password的解密
如果可以，我想尝试做一下这个需求

Start by tracing how the storage layer loads database and Redis usernames, passwords, host, and master name from configuration. Inspect the existing extension points and credential handling before deciding where a user-provided decryption interface belongs. Done means the design clearly supports non-plaintext credentials for both database and Redis configuration without breaking existing usage.

Written by the indexing model from the issue text.