fix: Add Windows compatibility for CLI and shell tools (#259)

[tanghoong]

Introduces platform-specific handling for terminal input and external editor selection, enabling full Windows 11 support. The CLI now uses msvcrt for keyboard input on Windows and sets Notepad as the default editor, while the shell middleware defaults to PowerShell on Windows for improved compatibility. Documentation is updated to reflect these changes and provide installation guidance for Windows users.

[eyurtsev]

We'd need to set up testing for this on CI for windows machines

[tanghoong]

We'd need to set up testing for this on CI for windows machines

Yes, I noticed that some behaviors still need improvement during the 'approval' and 'rejected' actions in the CLI.

[yangysc]

I really need the windows support since the text editor would crush on windows. Hope this can be merged ASAP...