[FEATURE] Add a Locale change tool

### Pre-flight checklist

- [x] I have searched existing issues/PRs and this has not been requested before.
- [x] I have read the [Contributing Guidelines](https://github.com/CachyOS/linux-cachyos/blob/master/CONTRIBUTING.md).

### Request type

- [ ] New patch / patchset inclusion
- [ ] Kernel config change (enable/disable option)
- [ ] New kernel variant
- [ ] Scheduler tuning / addition
- [ ] Compiler / LTO / PGO optimization
- [ ] Security hardening
- [ ] Driver or hardware enablement
- [x] Other

### Summary

On a fresh install Arch always defaults you to the default 12h US locale format. Even if you set your geolocation during the installation. Would it be possible to add some kinda GUI tool or option that will enable you to switch to a diffrent locale, 24h format and have the first day of the week be Monday instead of the default Sunday. Can you add any simple GUI tool or setting that will make it easier to change that?

### Motivation / use case

If you use the default KDE and GNOME desktop enviroment then this is easy to change without issue, but if you use a diffrent desktop enviroment or a tilingwm you have go to etc/locale.gen and # out the locales that you need. For the 24 hour format you have to modify the LC_TIME in etc/locale.conf same problem if you want to set Monday for first day of the week.

### Patch / upstream reference (if available)

N/A

### Testing / benchmarks

N/A

### Additional context

Example would be MX Linux it has a Locale change option in it's MX tools or Ubuntus Language support tool available for all official flavours you set your locale and reboot the system it will change everything. It would be easier then having to edit everything manually in terminal if you don't use KDE or GNOME. There is also the is the ATT Arch Tweak tool created by [Erik Dubois ](https://github.com/erikdubois)that was made for the discontinued Arco Linux, but you have to add the nemesis repo for it to work.

ATT:
https://github.com/kirodubes/archlinux-tweak-tool-gtk4/tree/main