Cygwin/MSYS2 pty support

[ysc3839]

Is your feature request related to a problem? Please describe.
When execute tmux on Cygwin or MSYS2 with tabby, tmux exited with open terminal failed: not a terminal.
However tmux works well with mintty.

Describe the solution you'd like
IIRC mintty is using Cygwin/MSYS2 pty API. Tabby should also use pty instead of Windows console host.

Describe alternatives you've considered
None

Additional context
Related issue: #2319

[ysc3839]

@Eugeny Hello, did you forget this issue?

[Eugeny]

This seems to be an issue with MSYS2 itself reporting a different tty device when not running in its own terminal - the same happens for other terminals too: vercel/hyper#3608 alacritty/alacritty#1687 microsoft/terminal#5132

[ysc3839]

I think the correct solution is to use Cygwin pty directly, without going through Windows Console.
Maybe it's because Windows Console is not fully compatible with UNIX tty, so Cygwin report it's not a try.
My solution is to write a connector executable using C++, running in Cygwin environment, and communicate with tabby main process using ZeroMQ.