setup backup pipeline

modules/hardware/backup.nix

@@ -9,6 +9,10 @@
         key = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIDU2NJ9xwYnp6/frIOv96ih8psiFcC2eOQeT+ZEMW5rq";
         roles = [ "source" "info" "send" ];
       }
+      {
+        key = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIIma7jNVQZM+lFMOKUex0+cyDpeUA3Wo4SEJ7P9YnHPG";
+        roles = [ "target" "info" "receive" ];
+      }
     ];
   };
 }