add update2: local eval+build fallback on the clients

common.nix

@@ -145,6 +145,9 @@ in
       if config.networking.hostName == "FredOS-Mediaserver"
       then localUpdate
       else remoteUpdate;
+    # Fallback for when the server is down or the alias itself changed and the
+    # live generation still has the old one: eval and build right here.
+    update2 = localUpdate;
     clean = "sudo nix-collect-garbage -d";
     # Throw away the VM's disk first so every run is a real first boot —
     # greeter, Plasma first-run, the lot. Builds into ./result in $PWD.