docs: improve commands generation

[cfabianski]

Description

closes #1410 #1245

Improve the doc generation.
I needed to have an accessor to the env variables defined in viper so I forked Viper and I made those changes spf13/viper@f9bd0ac

Another approach would have been not rely on the Cobra commands at all and instead use only the code and Flags we defined ourselves.
I discarded this option as I wanted my changes to be portable to Cobra, Viper, PFlags if we wanted.

Checklist

• I've added test coverage that shows my fix or feature works as expected.
• I've updated or added documentation if required.
• I've included usage information in the description if CLI behavior was updated or added.
• PR title follows Conventional Commits format