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/@eslint/eslintrc/lib/config-array/index.js

@@ -0,0 +1,19 @@
+/**
+ * @fileoverview `ConfigArray` class.
+ * @author Toru Nagashima <https://github.com/mysticatea>
+ */
+
+import { ConfigArray, getUsedExtractedConfigs } from "./config-array.js";
+import { ConfigDependency } from "./config-dependency.js";
+import { ExtractedConfig } from "./extracted-config.js";
+import { IgnorePattern } from "./ignore-pattern.js";
+import { OverrideTester } from "./override-tester.js";
+
+export {
+    ConfigArray,
+    ConfigDependency,
+    ExtractedConfig,
+    IgnorePattern,
+    OverrideTester,
+    getUsedExtractedConfigs
+};