feat: automatically produce the configuration documentation

[mauromorales]

Right now this page https://kairos.io/docs/reference/configuration/ describes all the possible configurations in Kairos. The content is written manually so it's easy that some configuration options are outdated, or that new ones are added but don't comply with the validator for example.

I would like to have a system that knowing the kairos version, it will produce all the actual possible configurations that system can have. If something is missing, it needs to be added to the single source of truth, if something is not supposed to be there, it needs to be removed from the single source of truth.