Add selector $select_file

[verside2]

Problem description

I need to create command for certain file in command pallete:

{
  "caption": "Rm: unwatch file",
  "command": "git",
  "args": {"argv": ["rm", "--cached", "last.txt"]}
}

As an alternative, I can use $text for file name.

Preferred solution

It would be more convenient to be able to use selector $select_file, which would work the same way as the selection in the file_history command.

{
  "caption": "Rm: unwatch file",
  "command": "git",
  "args": {"argv": ["rm", "--cached", "$select_file"]}
}