Add zsh function to spawn graphical application in the background

modules/graphical/compositor/default.nix

@@ -190,7 +190,8 @@ in
         pkgs.wf-recorder
         pkgs.wl-clipboard
       ];
-      programs.waybar = {
+      programs = {
+        waybar = {
           enable = true;
           settings = {
             mainBar = {
@@ -347,6 +348,12 @@ in
           '';
           systemd.enable = true;
         };
+        zsh.initExtra = ''
+          rs() {
+            riverctl spawn "$*"
+          }
+        '';
+      };
       services = {
         kanshi = {
           enable = true;