feat: add configure-grub just command

[dreamyukii]

based on bazzite configure grub just command with command from hidden grub changeset

[bketelsen]

i'll let others comment here too, but I think we're trying to reduce the amount of inline bash scripting in our just files and instead put an actual script on disk and call it from just.

[dreamyukii]

i'll let others comment here too, but I think we're trying to reduce the amount of inline bash scripting in our just files and instead put an actual script on disk and call it from just.

done, is /usr/libexec the correct location for the script?

[m2Giles]

Quick comments. menu_auto_hide=2 always hides. Additionally your condition check will say the grub menu is hidden even when it's not.

I think you should have 3 states.

Always Hide, Auto Hide, and Not Hidden. Auto Hide should be the default behaviour on new installs.

Thank you for adding this, and it will be a great place to put the rest of grub logic like removing duplicate entries and regenerating grub.cfg

[dreamyukii]

thank you for adding check for grub state