Unfortuately, it's manual :) Keyboard shortcut to put the text into the clipboard and then paste it into the comment.
If you're on linux using X11
#!/usr/bin/env nix-shell
#!nix-shell -i bash --packages xautomation xclip
sleep 0.2
printf '[Anti Commercial-AI license](https://creativecommons.org/licenses/by-nc-sa/4.0/)' | xclip -selection clipboard
#(echo ' spoiler Anti Commercial AI thingy
#[CC BY-NC-SA 4.0](https://creativecommons.org/licenses/by-nc-sa/4.0/)
#
#Inserted with a keystroke running this script on linux with X11
#```bash'
#cat "$0"
#echo '```
#:::') | xclip -selection clipboard
xte "keydown Control_L" "key V" "keyup Control_L"
:::