Replaced the Mergo package from "github.com/imdario/mergo" to "dario.cat/mergo". This change was necessary due to the new release from the Mergo package which includes bug fixes and performance improvements.
Moreover, updated the Go version from 1.20 to 1.21.1, including the toolchain version to stay up to date with the latest language features and bug fixes.
Lastly, other dependencies were updated and cleaned up for maintaining package stability and compatibility.
update: add eTag on fetch users for save resources
update: split cert monitor service
update: refactor log format
update: add support shadowsocks_2022
The cert monitor period = UpdatePeriodic * 60
The xray-core official is not implementation of proxy.UserManager feature. So it may change in the future.
