✨ feat(vendor): add playbook snapshot generation

tests/cli/test_playbook_cli.py

@@ -47,5 +47,23 @@ langs = ["tsl"]
         self.assertIn("sync_standards", output)
         self.assertIn("format_md", output)
 
+    def test_vendor_creates_snapshot(self):
+        with tempfile.TemporaryDirectory() as tmp_dir:
+            config_body = f"""
+[playbook]
+project_root = "{tmp_dir}"
+
+[vendor]
+langs = ["tsl"]
+"""
+            config_path = Path(tmp_dir) / "playbook.toml"
+            config_path.write_text(config_body, encoding="utf-8")
+
+            result = run_cli("-config", str(config_path))
+
+            snapshot = Path(tmp_dir) / "docs/standards/playbook/SOURCE.md"
+            self.assertEqual(result.returncode, 0)
+            self.assertTrue(snapshot.is_file())
+
 if __name__ == "__main__":
     unittest.main()