feat(murmur): Add Mumble server

modules/nixos/impermanence.nix

@@ -69,6 +69,14 @@ in {
       name = cfg.persistGroupName;
     };
 
+    systemd.tmpfiles.settings."10-varlibprivate" = {
+      "/var/lib/private" = {
+        z.group = "root";
+        z.user = "root";
+        z.mode = "2700";
+      };
+    };
+
     # Permit members of `cfg.persistGroupName` to read, write, and execute
     # /persist.
     systemd.tmpfiles.settings."10-persist" = {