[FEATURE] cachyos-update notification for root passwort input prompt

Hey!

If you run `cachyos-update` while working and switch to another window, you can sometimes forget to enter the root password to start the update process or to confirm changes.

Therefore, it would be great if it could make use of the system notification service to notify the user with a message like: **"CachyOS Updater: root password required."**

Small change, improved UX. :)

All the best

Start by locating the cachyos-update entry point and the code that requests the root password or confirms changes. Check how the system notification service is invoked, then verify that a notification with the requested message appears when input is needed and that the update flow still proceeds normally.

Written by the indexing model from the issue text.