refactor(clustering) dpcp config clean

[chronolaw]

Summary

DP/CP's code is too complex and not human readable, it is hard to understand the callback workflows.

This PR separates the logic of update_config, moves the code into an isolated file,
and also de-coupled dp/cp modules.

This PR is same as #8880, but solved the merge conflict of #8888.

Full changelog

• separates the logic of update_config into config_helper.lua
• do not use self to mimic oop
• remove duplicated functions extract_major_minor and validate_shared_cert in wrpc_cp
• add many functions in utils.lua
• remove version_handshake
• pick perf(*) make some heavily used code paths more cooperative by yielding #8888's yield feature in to_sorted_string
• update config hash test case

[fffonion]

as the changeset is relatively large, my eye may miss something, so i'm relying on the tests to ensure it doesn't break. I went through the code from high level of view and didn't find obvious errors.