Tools growing unexpected code execution is how we keep having problems with secrets and other important things being stolen. If you add this feature to git, generally, then anybody cloning a git repo is going to have to deal with the fact that `git clone` might run arbitrary code. `git clone` is like `cp`. Do you want `cp` to unexpectedly run code? It should never do that.

Why force git to be a build tool?

Just document how to execute the scripts/checks that will be used by ci. Provide a simple script in the repo that folks can intentionally execute.

Git is already a build tool and LFS is a great example of something git should be able to do and is also an example of how bolted on these things feel because of pointless push back in talking about a real solution.

You don't need to bring up bad ideas as if it precludes the existence of good ideas. Let's talk about good ways to solve these problems and improve the tool.