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/tabs/tab.js

@@ -0,0 +1,41 @@
+import { createElement } from "react";
+/**
+ * WordPress dependencies
+ */
+
+import { forwardRef } from '@wordpress/element';
+
+/**
+ * Internal dependencies
+ */
+
+import warning from '@wordpress/warning';
+import { useTabsContext } from './context';
+import { Tab as StyledTab } from './styles';
+export const Tab = forwardRef(function Tab({
+  children,
+  tabId,
+  disabled,
+  render,
+  ...otherProps
+}, ref) {
+  const context = useTabsContext();
+  if (!context) {
+    typeof SCRIPT_DEBUG !== "undefined" && SCRIPT_DEBUG === true ? warning('`Tabs.Tab` must be wrapped in a `Tabs` component.') : void 0;
+    return null;
+  }
+  const {
+    store,
+    instanceId
+  } = context;
+  const instancedTabId = `${instanceId}-${tabId}`;
+  return createElement(StyledTab, {
+    ref: ref,
+    store: store,
+    id: instancedTabId,
+    disabled: disabled,
+    render: render,
+    ...otherProps
+  }, children);
+});
+//# sourceMappingURL=tab.js.map