TL;DR - this plugin automatically backs up all your scripts whenever you change them, with no configuration required. Just download it and put it to your plugins folder.

Extended description:
This plugin copies all files that are in plugins/Skript/scripts and end with .sk to plugins/Skript/backups/scripts/script-name.sk/script-name-current-date-current-time.sk. This is done every time you change the script in any way while the server is running, as well as on the server startup, if the script was modified while the server was off.

Subdirectories like plugins/Skript/scripts/idk1/idk2/idk3/script.sk are supported too.

That's it. Enjoy!

The source code: https://github.com/Nicofisi/Baskup

NB: I may add an option to limit the amount of backups or something else if enough people request it. If you need something, definitely please let me know <3