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/@wordpress/components/build-module/style-provider/index.js

@@ -0,0 +1,50 @@
+import { createElement } from "react";
+/**
+ * External dependencies
+ */
+import { CacheProvider } from '@emotion/react';
+import createCache from '@emotion/cache';
+import * as uuid from 'uuid';
+
+/**
+ * Internal dependencies
+ */
+
+const uuidCache = new Set();
+// Use a weak map so that when the container is detached it's automatically
+// dereferenced to avoid memory leak.
+const containerCacheMap = new WeakMap();
+const memoizedCreateCacheWithContainer = container => {
+  if (containerCacheMap.has(container)) {
+    return containerCacheMap.get(container);
+  }
+
+  // Emotion only accepts alphabetical and hyphenated keys so we just
+  // strip the numbers from the UUID. It _should_ be fine.
+  let key = uuid.v4().replace(/[0-9]/g, '');
+  while (uuidCache.has(key)) {
+    key = uuid.v4().replace(/[0-9]/g, '');
+  }
+  uuidCache.add(key);
+  const cache = createCache({
+    container,
+    key
+  });
+  containerCacheMap.set(container, cache);
+  return cache;
+};
+export function StyleProvider(props) {
+  const {
+    children,
+    document
+  } = props;
+  if (!document) {
+    return null;
+  }
+  const cache = memoizedCreateCacheWithContainer(document.head);
+  return createElement(CacheProvider, {
+    value: cache
+  }, children);
+}
+export default StyleProvider;
+//# sourceMappingURL=index.js.map