feat: add test placeholder with node:test runner

Add test/ directory with a smoke test suite using Node.js built-in
test runner (node:test). Tests verify package.json fields, CLI entry
point, lib modules, and slash command files exist. Add "test" script
to package.json so npm test works out of the box for contributors.

Co-Authored-By: Claude Opus 4.6 <[email protected]>

Author: 2 people

package.json

@@ -14,6 +14,7 @@
   "scripts": {
     "build": "pkgroll --clean-dist --src .",
     "dev": "pkgroll --watch --src .",
+    "test": "node --test 'test/**/*.test.cjs'",
     "prepublishOnly": "npm run build"
   },
   "dependencies": {

test/mgw.test.cjs

@@ -0,0 +1,75 @@
+/**
+ * MGW — Placeholder test suite
+ *
+ * This file establishes the test directory and a minimal smoke test.
+ * Future contributors should add tests here for:
+ *
+ *   - CLI argument parsing (bin/mgw.cjs)
+ *   - State file read/write (lib/state.cjs)
+ *   - Template loading (lib/template-loader.cjs)
+ *   - Output formatting (lib/output.cjs)
+ *   - GitHub helpers (lib/github.cjs)
+ *
+ * Run with: npm test
+ *
+ * The test uses Node's built-in assert module and test runner (node:test)
+ * which requires Node.js >= 18. No additional test dependencies needed.
+ */
+
+const { describe, it } = require('node:test');
+const assert = require('node:assert/strict');
+const { existsSync } = require('node:fs');
+const { resolve } = require('node:path');
+
+describe('mgw', () => {
+  it('package.json exists and has required fields', () => {
+    const pkgPath = resolve(__dirname, '..', 'package.json');
+    assert.ok(existsSync(pkgPath), 'package.json should exist');
+
+    const pkg = require(pkgPath);
+    assert.ok(pkg.name, 'package.json should have a name');
+    assert.ok(pkg.version, 'package.json should have a version');
+    assert.ok(pkg.bin, 'package.json should have a bin field');
+    assert.ok(pkg.main, 'package.json should have a main field');
+  });
+
+  it('CLI entry point exists', () => {
+    const binPath = resolve(__dirname, '..', 'bin', 'mgw.cjs');
+    assert.ok(existsSync(binPath), 'bin/mgw.cjs should exist');
+  });
+
+  it('lib modules exist', () => {
+    const libDir = resolve(__dirname, '..', 'lib');
+    const expectedModules = [
+      'index.cjs',
+      'state.cjs',
+      'github.cjs',
+      'output.cjs',
+      'gsd.cjs',
+      'claude.cjs',
+      'template-loader.cjs',
+      'templates.cjs',
+    ];
+
+    for (const mod of expectedModules) {
+      const modPath = resolve(libDir, mod);
+      assert.ok(existsSync(modPath), `lib/${mod} should exist`);
+    }
+  });
+
+  it('commands directory has expected slash commands', () => {
+    const cmdDir = resolve(__dirname, '..', 'commands');
+    const expectedCommands = [
+      'run.md',
+      'issue.md',
+      'init.md',
+      'status.md',
+      'sync.md',
+    ];
+
+    for (const cmd of expectedCommands) {
+      const cmdPath = resolve(cmdDir, cmd);
+      assert.ok(existsSync(cmdPath), `commands/${cmd} should exist`);
+    }
+  });
+});