before functional changes by codex

test/basic/structure-module-load.basic.test.js

@@ -0,0 +1,8 @@
+const test = require('node:test');
+const assert = require('node:assert/strict');
+
+test('valveGroupControl module load smoke', () => {
+  assert.doesNotThrow(() => {
+    require('../../vgc.js');
+  });
+});