add two-vm wg-hive mesh test to vmTests

nix/vm-tests.nix

@@ -1,8 +1,13 @@
 # NixOS VM tests: one derivation per test, exposed as `vmTests.<system>.<name>`.
 # Kept out of `checks` because each boots VMs and needs KVM; the nightly
 # workflow `.forgejo/workflows/vm-nightly.yml` builds them.
-{ pkgs, hivePriv }:
+{
+  pkgs,
+  hivePriv,
+  self,
+}:
 {
   agent-ephemeral-rootfs = import ./vm-tests/agent-ephemeral-rootfs.nix { inherit pkgs hivePriv; };
+  wg-hive = import ./vm-tests/wg-hive.nix { inherit pkgs self; };
   hive-squid = import ./vm-tests/hive-squid.nix { inherit pkgs; };
 }