greeter: New Greeter Settings UI & Sync fixes

- Add PAM Auth via GUI
- Added new sync flags
- Refactored cache directory management & many others
- Fix for wireplumber permissions
- Fix for polkit auth w/icon
- Add pam_fprintd timeout=5 to prevent 30s auth blocks when using password

quickshell/Modals/Settings/SettingsSidebar.qml

@@ -281,6 +281,12 @@ Rectangle {
                     "icon": "lock",
                     "tabIndex": 11
                 },
+                {
+                    "id": "greeter",
+                    "text": I18n.tr("Greeter"),
+                    "icon": "login",
+                    "tabIndex": 31
+                },
                 {
                     "id": "power_sleep",
                     "text": I18n.tr("Power & Sleep"),