add radish-vm for testing

hosts/radish-vm/default.nix

@@ -0,0 +1,24 @@
+{ inputs, ... }:
+let
+  inherit (inputs)
+    home-manager
+    ;
+in
+{
+  imports = [
+    ./hardware-configuration.nix
+    # Import most of the original radish config
+    ../radish/configuration.nix
+    ../radish/host.nix
+    ../radish/packages.nix
+    ../radish/containers.nix
+    ../radish/desktop.nix
+    ../radish/users.nix
+    ../radish/secrets.nix
+    # VM-specific overrides
+    ./boot.nix
+    ./hardware.nix
+    home-manager.nixosModules.home-manager
+    ../../home
+  ];
+}