CLI tooling

[billti]

We currently have a CLI build at part of the repo, but we don't ship it. Long term, do we need some type of CLI support?

Note that this could be a simple as a CLI added to the environment by "pip install qsharp" (e.g. https://packaging.python.org/en/latest/guides/creating-command-line-tools/ ).

Imagining for now a CLI named qsharp, perhaps this could contain subcommands such as qsharp compile ..., qsharp run ..., qsharp test ..., etc.

This would also be useful for Copilot to run commands in agent mode in editors or repo bots (e.g. to run simulations and/or verify changes).

[swernli]

Regarding the approach of using a Python-based cmdline tool, @idavis prototyped this a while back in 6517954. Could be a good comparison point to dust that off and see how it integrates with the latest workflows.