Add Windows support for kill by process ID --from winuxcmd project

[a-rookie-of-C-language]

Summary

kill is currently not shipped in Coreutils for Windows because Windows does not provide POSIX signals. However, Windows can still terminate processes by process ID through native process APIs.

This issue proposes adding a Windows-specific kill implementation that supports PID-based process termination while clearly documenting that it is not full POSIX signal support.

Proposed behavior

Support commands such as:

kill <PID>
kill -9 <PID>
kill -KILL <PID>
kill -TERM <PID>
kill -s KILL <PID>
kill --signal=TERM <PID>
kill --list

[jbauerrfid]

When adding kill please don't forget ps.

The commands could also wrap pskill and pslist from Sysinternals.

[ipfred]

强烈需要这个功能 ps kill，windows中至今记不住如何用命令行查看进程

[a-rookie-of-C-language]

理解你们的需求,但是ps 命令并不属于coreutils process listing tool,是否添加可能还需要参考作者的意见,不过,你们可以参考我们的另一个项目,winuxcmd,它提供了ps命令,https://github.com/caomengxuan666/WinuxCmd

[caomengxuan666]

强烈需要这个功能 ps kill，windows中至今记不住如何用命令行查看进程

Good point. I also added ps into the PowerShell rewrite list in the PR, so bare ps should be routed to ps.cmd in interactive PowerShell, just like other commands.

About top, I think maybe we should discuss it in another issue. It is useful, and WinuxCmd already has one, but it is much bigger than ps because it needs refresh, terminal UI, sorting, CPU/memory stats, etc. So I don't want to make this PR too large.

Also, top may be even further away from coreutils scope, so I think it needs a maintainer decision first.