Python: Consider bundling `copilot` CLI as an optional dependency

[Lauszus]

I would be nice if copilot was not bundled inside the wheel, but was packaged as a separate wheel.

That would allow this wheel to include it as an optional dependency instead:

bin = [
    "copilot-cli",
]

The benefit is that all users would not have to download the bundled copilot CLI when using a custom agent that using copilot in headless mode running on a remote server.

It is quite easy to bundle as binary inside a wheel and make it the entry point. See for instance: https://github.com/ziglang/zig-pypi