Add support for Windows

[lstocchi]

Following my chat with Colin, I am opening this issue to track the exploration of enabling Windows for bcvk.
This issue serves as a high-level overview of the initial POC and a discussion point for the direction we want to take.

During DevTools week I have implemented a CLI POC that allows the project to work on Windows using Hyper-V.

• POC branch (experimental): Link
• main branch (a bit more polished/rebased on upstream): Link

the POC is very limited and only implements the to_disk and hyperv run commands. They are very far from the upstream implementation. My intent was more to put my hands over rust. It's not ready for testing as it is tightly coupled with my local setup. It requires podman to have a machine on WSL, macadam to be installed and that the bootc image to have the hyperv-daemons package in it.

This issue will be used as an Epic to track sub-issues that provides a minimal support on Windows.

@cgwalters if you prefer to not have any epic you can close it. I opened this as it was the only way i thought to give a quick overview why i was targeting windows.

Were you envisioning to have the windows implementation here or keep a separate project as it could be implemented slower than the linux version?
FYI in the bcvk_win main branch i tried to add my commits over bcvk.

Which is the minimal support bcvk should provide on Windows? Bootc VHD/VHDX image creation + running a permanent Hyper-v VM with that image? I'll open an issue for each command to separate discussions and avoid confusion.

• to_disk on Windows

[cgwalters]

Were you envisioning to have the windows implementation here or keep a separate project as it could be implemented slower than the linux version?

A complex question because I think roughly 80% of the code would not be shared, right?

That said...I guess my lean is it'd make sense to try to share that remaining 20%.

So one of the first commits there basically turns the entire project into a "stub" effectively on non-linux. I think we can do this a little bit better. Maybe one thing that we could do is have crates/bcvk_linux and crates/bcvk_windows for example.

We'd have then crates/bcvk_cli which would hold the shared bits (perhaps just some core clap structs?).

A prep commit could basically git mv crates/kit crates/bcvk_linux and then create the cli crate?

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Which is the minimal support bcvk should provide on Windows? Bootc VHD/VHDX image creation + running a permanent Hyper-v VM with that image?

I would really like to replicate the bcvk ephemeral core primitive because that means that generating disk images is just a special case of a more general tool.

See #21 - my understanding here is that Windows is probably similar.