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/devtools-protocol/README.md

@@ -0,0 +1,11 @@
+# devtools-protocol [![devtools-protocol on npm](https://img.shields.io/npm/v/devtools-protocol)](https://www.npmjs.com/package/devtools-protocol)
+
+:warning:
+This repository is related to Chrome DevTools Protocol, but does not track issues regarding its definition or implementation.
+If you want to file an issue for the Chrome DevTools Protocol, please open an issue on https://crbug.com under [`component: Platform>DevTools>Platform`](https://bugs.chromium.org/p/chromium/issues/entry?components=Platform%3EDevTools%3EPlatform).
+
+Use the [protocol viewer](https://chromedevtools.github.io/devtools-protocol/) for navigating the protocol.
+
+TypeScript definitions for the protocol's types are available in ['types/protocol.d.ts'](https://github.com/ChromeDevTools/devtools-protocol/tree/master/types). Mappings from Commands and events to these types are available in either generated `DomainApi` style in [`types/protocol-proxy-api.d.ts`](https://github.com/ChromeDevTools/devtools-protocol/blob/master/types/protocol-proxy-api.d.ts) or in simple name-to-type-interface style in [`types/protocol-mapping.d.ts`](https://github.com/ChromeDevTools/devtools-protocol/blob/master/types/protocol-mapping.d.ts).
+
+Also, this repo is published as the [`devtools-protocol`](https://www.npmjs.com/package/devtools-protocol) npm module.