Add a Prerequisite class to manage all initilaization prerequisites. Invoke before each request. Provide a CLI script to allow checking Prereqs from command line. Add CI workflow to confirm prereq validation behavior.
Reviewed-on: https://gitea.subcultureofone.org/greg/tkr/pulls/30
Co-authored-by: Greg Sarjeant <greg@subcultureofone.org>
Co-committed-by: Greg Sarjeant <greg@subcultureofone.org>
