refactor: refactor to relative user directories and new moonraker config dirs

[meteyou]

This PR contains:

• Change all /home/pi to ~/. This is necessary to have usernames independent paths
• Change github.com/raymondh to github.com/mainsail-crew (updated the repo of MainsailOS)
• Add download commands for the config/python files

[KiloQubit]

I just realized, probe_accuracy.py also has a reference to /home/pi in the comment, and in the default value for the --klippy-uds flag. Replacing it with ~ in the flag would require shell expansion before calling open(), because Python won't expand the ~ there.

[meteyou]

Thx! i fixed all issues and also refactored the proby_accuracy.py.

[KiloQubit]

Thanks @meteyou !