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/@jest/test-result/build/index.js

@@ -0,0 +1,40 @@
+'use strict';
+
+Object.defineProperty(exports, '__esModule', {
+  value: true
+});
+Object.defineProperty(exports, 'addResult', {
+  enumerable: true,
+  get: function () {
+    return _helpers.addResult;
+  }
+});
+Object.defineProperty(exports, 'buildFailureTestResult', {
+  enumerable: true,
+  get: function () {
+    return _helpers.buildFailureTestResult;
+  }
+});
+Object.defineProperty(exports, 'createEmptyTestResult', {
+  enumerable: true,
+  get: function () {
+    return _helpers.createEmptyTestResult;
+  }
+});
+Object.defineProperty(exports, 'formatTestResults', {
+  enumerable: true,
+  get: function () {
+    return _formatTestResults.default;
+  }
+});
+Object.defineProperty(exports, 'makeEmptyAggregatedTestResult', {
+  enumerable: true,
+  get: function () {
+    return _helpers.makeEmptyAggregatedTestResult;
+  }
+});
+var _formatTestResults = _interopRequireDefault(require('./formatTestResults'));
+var _helpers = require('./helpers');
+function _interopRequireDefault(obj) {
+  return obj && obj.__esModule ? obj : {default: obj};
+}