[Feature Request] greeter sync: make pkexec optional when run0 exist

[puiyq]

Submission checklist

• I have searched existing issues and confirmed this is not a duplicate.
• I am using the latest available version of Noctalia.

Bug description

The greeter syncer requires pkexec with the setuid bit enabled. However, I have disabled the pkexec wrapper on my system because I use run0 as my privilege escalator. run0 utilizes polkit for authentication without relying on setuid.

Steps to reproduce

1. Set up the Noctalia greeter.
2. Disable the pkexec wrapper (e.g., set security.wrappers.pkexec.enable = false on NixOS).
3. Attempt to sync the greeter from Noctalia settings.

Expected behavior

The greeter syncs successfully. (Verified that it works as expected when the pkexec setuid wrapper is enabled on my system).

Actual behavior

The sync process fails.

Logs / error output

Noctalia version

7421f80

Compositor

Niri

Distribution

NixOS

Environment information

Installation method: Nix Flake

Additional context

No response

[Ly-sec]

Hey @puiyq , while we don't accept feature requests currently I did fix it because it felt more like a bug / oversight on our end.
However I'd like you to test 8c634b5 because I do not use run0.
Please let me know if everything works now.

[puiyq]

it fail with

Jun 12 19:16:41 popipa noctalia[4510]: 19:16:41.114 [WRN] [greeter-sync] greeter sync failed: pkexec must be setuid root

might be because the pkexec is still on my PATH even I disable the setuid wrapper