[FEATURE] Allow to specify command defaults in (possible global) config file

[jeertmans]

Discussed in #534

^{Originally posted by Quaesius March 9, 2025}

TL;DR - OP suggests that we can specify command defaults in the config files, and probably also read from a global config file if it exists.

This requires quite a few additions, see #534 (comment), but I am in favor of this new feature! Any help is welcome!