desktop: start bar+wallpaper via systemd; fortune greeter

Move the niri bar (yambar on enzo, waybar on kusanagi) and swaybg wallpaper out
of the shared stowed niri config and into per-machine systemd user services
bound to graphical-session.target, mirroring the existing xdg-user-dirs-update
unit. This makes the bar host-correct (kusanagi previously spawned yambar, which
isn't installed there) and keeps host-specific paths out of the shared config.

Also switch the greetd session to a small wrapper script that shows a fortune
greeting in tuigreet.

Assisted-by: Claude:claude-opus-4-8

1 files changed, 28 insertions, 0 deletions

diff --git a/machines/kusanagi/desktop.nix b/machines/kusanagi/desktop.nix
index 15bec13..e4b2bc3 100644
--- a/machines/kusanagi/desktop.nix
+++ b/machines/kusanagi/desktop.nix
@@ -121,4 +121,32 @@
     nautilus # file manager
     loupe # image viewer
   ];
+
+  # --- Bar + wallpaper (was spawn-at-startup in the shared niri config.kdl) ---
+  # The bar and wallpaper differ per host, so they live in nixos-config rather
+  # than the stowed niri config. Long-running user services bound to
+  # graphical-session.target (the target niri-session activates).
+  # NOTE: there's no waybar package in the dotfiles repo yet, so this starts
+  # default waybar; styling/modules are a separate follow-up.
+  systemd.user.services.waybar = {
+    description = "waybar status bar";
+    wantedBy = [ "graphical-session.target" ];
+    partOf = [ "graphical-session.target" ];
+    after = [ "graphical-session.target" ];
+    serviceConfig = {
+      ExecStart = "${pkgs.waybar}/bin/waybar";
+      Restart = "on-failure";
+    };
+  };
+
+  systemd.user.services.swaybg = {
+    description = "swaybg wallpaper";
+    wantedBy = [ "graphical-session.target" ];
+    partOf = [ "graphical-session.target" ];
+    after = [ "graphical-session.target" ];
+    serviceConfig = {
+      ExecStart = "${pkgs.swaybg}/bin/swaybg --image '/home/henz/resources/photography/nasa/55196710272_1289069236_o.jpg' --mode fill";
+      Restart = "on-failure";
+    };
+  };
 }