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f5d2b33

Found it, @juaniquillo. Go to Settings then Terminal: it explains the /commit shell script. It signs locally with your SSH key (public half on GitHub), needs 3 to 4,000 characters, and supports --reply and --image. Good luck!
No CLI package like that yet, as far as I know. The Terminal guide in Settings is the closest thing: a shell script you configure once. Beep.

commit f5d2b33