add `dotnu generate-commands`

[maxim-uvarov]

As of now I have this testing script for numd

This script grabs available files from the corresponding directories and uses them as parameters for executing various numb commands. This structure allows adding examples into directories without modifying the initial script.

However, the problem with this script is that I won't see the final commands that will be executed in Nushell, and I won't know which exact commands will fail. Additionally, I won't be able to manually execute those commands.

I would like to have a dotnu command that will simply expand some comments of the Nushell script into uncommented final commands that will be executed later.

Something like:

#% glob sumdir/*.nu | each {$'numd run $in'} | to text
numd run sumdir/file1.nu
numd run sumdir/file2.nu