Open firewall for avahi

Hopefully this helps

hosts/modules/base.nix

@@ -90,6 +90,7 @@
       # domain = true; # Announce the locally used domain name (usually .local)
       # userServices = true; # Publish services advertised by users
     };
+    openFirewall = true;
     # If you're using systemd-resolved alongside Avahi, ensure mDNS is also enabled there:
     # services.resolved.enable = true;
     # services.resolved.extraConfig = "MulticastDNS=yes";