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/memfs/lib/Dirent.d.ts

@@ -0,0 +1,19 @@
+import { Link } from './node';
+import { TEncodingExtended, TDataOut } from './encoding';
+/**
+ * A directory entry, like `fs.Dirent`.
+ */
+export declare class Dirent {
+    static build(link: Link, encoding: TEncodingExtended | undefined): Dirent;
+    name: TDataOut;
+    private mode;
+    private _checkModeProperty;
+    isDirectory(): boolean;
+    isFile(): boolean;
+    isBlockDevice(): boolean;
+    isCharacterDevice(): boolean;
+    isSymbolicLink(): boolean;
+    isFIFO(): boolean;
+    isSocket(): boolean;
+}
+export default Dirent;