feature(greetd): add noctalia-greeter to greetd

Reviewed-on: #102

hosts/argon/configuration.nix

@@ -11,7 +11,7 @@
     ../../modules/nixos/certificates.nix
     ../../modules/nixos/data-drives.nix
     ../../modules/nixos/gnupg.nix
-    ../../modules/nixos/greetd.nix
+    ../../modules/nixos/noctalia-greeter.nix
     ../../modules/nixos/lanzaboote.nix
     ../../modules/nixos/locales.nix
     ../../modules/nixos/networking.nix

modules/nixos/noctalia-greeter.nix

@@ -0,0 +1,21 @@
+{
+  # greetd display manager with the graphical noctalia greeter, replaces greetd.nix.
+  # The nixpkgs module enables greetd, accountsservice (avatars) and polkit, and
+  # launches noctalia-greeter-session. Sessions (niri) are discovered from
+  # wayland-sessions, the last one picked is remembered.
+  # See https://docs.noctalia.dev/greeter/
+  services.displayManager.noctalia-greeter = {
+    enable = true;
+
+    # lets the shell's "Sync Now" / auto-sync copy wallpaper, palette and monitor
+    # layout to the greeter without an admin prompt (appearance only)
+    passwordlessSyncUsers = [ "aaron" ];
+
+    # rendered to /var/lib/noctalia-greeter/greeter.toml, wins over synced values
+    settings = {
+      user.default = "aaron";
+      # same layout as niri, otherwise the password is typed on a us keymap
+      keyboard.layout = "ch";
+    };
+  };
+}