chore(docs): Installing pixi in Github Copilot Agent environment

[amirhosseindavoody]

Problem description

Background

Github has added copilot agents where you can assign tasks like adding features or code refactoring to the agents. They run everything in the cloud and give you a pull request. Something like Github Actions but with some agent added.

The issue that I have is that it cannot install pixi in that environment, so it uses the vanilla python in the system path. See the screenshot below.

I tried adding this instruction, but it wasn't helpful

This agent uses pixi package manager for managing the python environment.

The relevant github action is prefix-dev/setup-pixi.

Alternatively we can install pixi using `curl -fsSL https://pixi.sh/install.sh | sh` command.

The environment needs to be activated using `pixi shell` before running further commands.

Alternatively, it can prepend any command with `pixi run` to execute the command inside the pixi environment.

[nichmor]

That's an interesting one! I think we need to update /adapt our documentation to this workflow