nixos/slimserver: Disable broken image/video support (#40589)

nixos/modules/services/audio/slimserver.nix

···
       serviceConfig = {
         User = "slimserver";
         PermissionsStartOnly = true;
-        ExecStart = "${cfg.package}/slimserver.pl --logdir ${cfg.dataDir}/logs --prefsdir ${cfg.dataDir}/prefs --cachedir ${cfg.dataDir}/cache";
+        # Issue 40589: Disable broken image/video support (audio still works!)
+        ExecStart = "${cfg.package}/slimserver.pl --logdir ${cfg.dataDir}/logs --prefsdir ${cfg.dataDir}/prefs --cachedir ${cfg.dataDir}/cache --noimage --novideo";
       };
     };