fix: prevent asset conflicts between React and Grid.js versions

Add coexistence checks to all enqueue methods to prevent loading
both React and Grid.js assets simultaneously.

Changes:
- ReactAdmin.php: Only enqueue React assets when ?react=1
- Init.php: Skip Grid.js when React active on admin pages
- Form.php, Coupon.php, Access.php: Restore classic assets when ?react=0
- Customer.php, Product.php, License.php: Add coexistence checks

Now the toggle between Classic and React versions works correctly.

Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>

node_modules/babel-runtime/helpers/inherits.js

@@ -0,0 +1,33 @@
+"use strict";
+
+exports.__esModule = true;
+
+var _setPrototypeOf = require("../core-js/object/set-prototype-of");
+
+var _setPrototypeOf2 = _interopRequireDefault(_setPrototypeOf);
+
+var _create = require("../core-js/object/create");
+
+var _create2 = _interopRequireDefault(_create);
+
+var _typeof2 = require("../helpers/typeof");
+
+var _typeof3 = _interopRequireDefault(_typeof2);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+exports.default = function (subClass, superClass) {
+  if (typeof superClass !== "function" && superClass !== null) {
+    throw new TypeError("Super expression must either be null or a function, not " + (typeof superClass === "undefined" ? "undefined" : (0, _typeof3.default)(superClass)));
+  }
+
+  subClass.prototype = (0, _create2.default)(superClass && superClass.prototype, {
+    constructor: {
+      value: subClass,
+      enumerable: false,
+      writable: true,
+      configurable: true
+    }
+  });
+  if (superClass) _setPrototypeOf2.default ? (0, _setPrototypeOf2.default)(subClass, superClass) : subClass.__proto__ = superClass;
+};