Is your feature request related to a problem? Please describe.
For security I use rbw bitwarden client to secure my keys. I do not leave them in the environment all the time, so I have a wrapper script for mods that gets all my API keys in parallel. It does not know what model I am going to request, so it must grab all of them.

Describe the solution you'd like
I would like a per api key in the config file api-key-cmd that runs the given command to get the API key, like many other programs do when requiring keys or passwords.

Describe alternatives you've considered
I have a wrapper script, but it would be cleaner and useful to others to implement api-key-cmd