hyprland: init `hyprpaper` service

[trueNAHO]

About

This is a tracking issue for initiating the hyprpaper service.

Steps

• [x] https://github.com/danth/stylix/pull/377
• [ ] unload wallpaper

Unresolved Questions

• [ ] How to unload the wallpaper: https://github.com/danth/stylix/pull/377#issuecomment-2143073614?