Sorry for the current state of sisu in Debian (and to some extent in Ruby more generally). (and for the top posting here).
I have a version of sisu working with ruby 3.0 & 3.1 (it can be run straight from the command line) ... but not made a deb of and built with Debian dependencies. Certainly the latex/pdf output has not been tested.
Also there remain a couple of issues to check.
I am not against Debian-live shipping documentation independently but will try to make sure sisu works as it should, (though I may request help packaging it once at that point).
You may follow up on my progress here or directly with me.
Thanks,
Ralph Amissah