[Question] Why does adding the modernization agent to GitHub Copilot Coding Agent require setting up a workflow with GitHub Copilot CLI?

### Description

[The instructions in for setting up the modernization agent in GitHub Copilot Coding Agent](https://github.com/dotnet/modernize-dotnet/tree/main/coding-agent#2-add-the-setup-steps) state that you must add a workflow to setup the GitHub Copilot CLI as a part of adding the modernization agent to Github Copilot Coding Agent.

The coding agent is supposed to already have an ephemeral environment for using GitHub Copilot, the .NET SDK and accessing the repository clone - why do we need to setup a "hand crafted", manually maintained version of this?

Bonus question; Why does the example workflow reference an old major version (20) of Node that is [EOL on 2026-04-30](https://github.com/nodejs/release#release-schedule) - is there some compatibility issue with newer versions? [The GitHub Copilot CLI docs state Node 22+](https://docs.github.com/en/copilot/how-tos/copilot-cli/set-up-copilot-cli/install-copilot-cli#installing-with-npm-all-platforms) as a requirement for installing the CLI with NPM.