wip: add first olivetin tests

modules/game/server/luanti/olivetin.nix

@@ -0,0 +1,19 @@
+{ pkgs, ... }: {
+  services.olivetin = {
+    enable = true;
+    settings = {
+      actions = [
+        {
+          title = "Hello world!";
+          shell = "echo 'Hello World!'";
+          popupOnStart = "execution-dialog-stdout-only";
+        }
+      ];
+    };
+
+    path = with pkgs; [
+      bash
+      git
+    ];
+  };
+}