feature: completion command

[raspher]

I've seen many go packages provide completion command which generates autocompletion script for multiple shells. Maybe scripthaus can provide that command too?

How it would work:
scripthaus completion bash - write to stdout a shell script which provides completion.

Commonly used shells:

• bash
• fish
• powershell
• zsh

I don't know much golang, but i've found project which does that - https://github.com/j178/leetgo