Bash shell uses readline for this, which I would guess is the namesake of PSReadLine:

https://wiki.archlinux.org/title/Readline
https://man.archlinux.org/man/readline.3#DEFAULT_KEY_BINDINGS

The “Alphorn”, the costume? Clearly Swiss coded. And French is one of several native languages in Switzerland, so not like the language is a clear hint towards the question of who they are supposed to depict.