Fun config 改进，兼容 aliyun cli profile

最近在弄一些 ROS 模板，有些付费的资源用个人账号玩不转，希望能有个 profile 功能，能方便地切换账号。这块 aws 和 aliyun cli 都有，当前的 fun config 来自于 fcli，而如今 fcli 已经不如 fun 活跃了，当时 fcli 的配置文件设计得也不太好，对于 internel 类型的 endpoint 支持起来不方便，所以建议改进一下。

Start by locating the fun config implementation and reviewing how the existing fcli configuration is handled. Compare the profile behavior of the AWS and Aliyun CLIs, including support for internal endpoints, and define the account-switching and configuration outcomes that would mark this feature complete.

Written by the indexing model from the issue text.