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/@webpack-cli/info/lib/index.d.ts

@@ -0,0 +1,5 @@
+import { type IWebpackCLI } from "webpack-cli";
+declare class InfoCommand {
+    apply(cli: IWebpackCLI): Promise<void>;
+}
+export default InfoCommand;

node_modules/@webpack-cli/info/lib/index.js

@@ -0,0 +1,17 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+class InfoCommand {
+    async apply(cli) {
+        await cli.makeCommand({
+            name: "info",
+            alias: "i",
+            description: "Outputs information about your system.",
+            usage: "[options]",
+            pkg: "@webpack-cli/info",
+        }, cli.getInfoOptions(), async (options) => {
+            const info = await cli.getInfoOutput(options);
+            cli.logger.raw(info);
+        });
+    }
+}
+exports.default = InfoCommand;