This updates canto-daemon to version 0.9.7 and canto-curses to version
0.9.9. I've tested building both and executing them (although without
very comprehensive tests) and they do work on my machine.
I haven't tested the NixOS service module however, but given that
@devhell is also the maintainer of these packages and the service
module, I trust that he's done testing by himself.