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-module-utils/moduleVisitor.d.ts

@@ -0,0 +1,26 @@
+import type { Rule } from 'eslint';
+import type { Node } from 'estree';
+
+type Visitor = (source: Node, importer: unknown) => any;
+
+type Options = {
+    amd?: boolean;
+    commonjs?: boolean;
+    esmodule?: boolean;
+    ignore?: string[];
+};
+
+declare function moduleVisitor(
+    visitor: Visitor,
+    options?: Options,
+): object;
+
+export default moduleVisitor;
+
+export type Schema = NonNullable<Rule.RuleModule['schema']>;
+
+declare function makeOptionsSchema(additionalProperties?: Partial<Schema>): Schema
+
+declare const optionsSchema: Schema;
+
+export { makeOptionsSchema, optionsSchema };