Make sparky a NFS backup instead of desktop.

hosts/sparky/default.nix

@@ -3,9 +3,10 @@
   imports = [
     ../../common/encrypted-btrfs-layout.nix
     ../../common/global
-    ../../common/desktop-node.nix     # Hyprland + GUI environment
-    ../../common/cluster-member.nix  # Consul + storage clients
-    ../../common/cluster-tools.nix    # Nomad CLI (no service)
+    ../../common/cluster-member.nix
+    ../../common/cluster-tools.nix
+    ../../common/nomad-worker.nix
+    ../../nfs-services-standby.nix
     ./hardware.nix
   ];