[FR] Add local configuration

[chenxudong2020]

Feature description

I also want to add user and password authentication to the local agent. Due to the network environment, github cannot be accessed, but hiddify needs to download files from github. Please add it to the configuration file. The link below is my merge request. If the above is not completed, please request the official addition. If you have the above configuration, it can be better applied to container environments such as s6 overlay, but the LAN proxy will be more secure
hiddify/hiddify-core#94