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/toolbar/toolbar-button/index.js

@@ -0,0 +1,93 @@
+import { createElement } from "react";
+/**
+ * External dependencies
+ */
+import classnames from 'classnames';
+/**
+ * WordPress dependencies
+ */
+import { useContext, forwardRef } from '@wordpress/element';
+
+/**
+ * Internal dependencies
+ */
+import Button from '../../button';
+import ToolbarItem from '../toolbar-item';
+import ToolbarContext from '../toolbar-context';
+import ToolbarButtonContainer from './toolbar-button-container';
+function UnforwardedToolbarButton({
+  children,
+  className,
+  containerClassName,
+  extraProps,
+  isActive,
+  isDisabled,
+  title,
+  ...props
+}, ref) {
+  const accessibleToolbarState = useContext(ToolbarContext);
+  if (!accessibleToolbarState) {
+    return createElement(ToolbarButtonContainer, {
+      className: containerClassName
+    }, createElement(Button, {
+      ref: ref,
+      icon: props.icon,
+      label: title,
+      shortcut: props.shortcut,
+      "data-subscript": props.subscript,
+      onClick: event => {
+        event.stopPropagation();
+        // TODO: Possible bug; maybe use onClick instead of props.onClick.
+        if (props.onClick) {
+          props.onClick(event);
+        }
+      },
+      className: classnames('components-toolbar__control', className),
+      isPressed: isActive,
+      disabled: isDisabled,
+      "data-toolbar-item": true,
+      ...extraProps,
+      ...props
+    }, children));
+  }
+
+  // ToobarItem will pass all props to the render prop child, which will pass
+  // all props to Button. This means that ToolbarButton has the same API as
+  // Button.
+  return createElement(ToolbarItem, {
+    className: classnames('components-toolbar-button', className),
+    ...extraProps,
+    ...props,
+    ref: ref
+  }, toolbarItemProps => createElement(Button, {
+    label: title,
+    isPressed: isActive,
+    disabled: isDisabled,
+    ...toolbarItemProps
+  }, children));
+}
+
+/**
+ * ToolbarButton can be used to add actions to a toolbar, usually inside a Toolbar
+ * or ToolbarGroup when used to create general interfaces.
+ *
+ * ```jsx
+ * import { Toolbar, ToolbarButton } from '@wordpress/components';
+ * import { edit } from '@wordpress/icons';
+ *
+ * function MyToolbar() {
+ *   return (
+ *		<Toolbar label="Options">
+ *			<ToolbarButton
+ *				icon={ edit }
+ *				label="Edit"
+ *				onClick={ () => alert( 'Editing' ) }
+ *			/>
+ *		</Toolbar>
+ *   );
+ * }
+ * ```
+ */
+export const ToolbarButton = forwardRef(UnforwardedToolbarButton);
+export default ToolbarButton;
+//# sourceMappingURL=index.js.map

node_modules/@wordpress/components/build-module/toolbar/toolbar-button/toolbar-button-container.js

@@ -0,0 +1,13 @@
+import { createElement } from "react";
+/**
+ * Internal dependencies
+ */
+
+const ToolbarButtonContainer = ({
+  children,
+  className
+}) => createElement("div", {
+  className: className
+}, children);
+export default ToolbarButtonContainer;
+//# sourceMappingURL=toolbar-button-container.js.map

node_modules/@wordpress/components/build-module/toolbar/toolbar-button/toolbar-button-container.js.map

@@ -0,0 +1 @@
+{"version":3,"names":["ToolbarButtonContainer","children","className","createElement"],"sources":["@wordpress/components/src/toolbar/toolbar-button/toolbar-button-container.tsx"],"sourcesContent":["/**\n * Internal dependencies\n */\nimport type { ToolbarButtonContainerProps } from './types';\n\nconst ToolbarButtonContainer = ( {\n\tchildren,\n\tclassName,\n}: ToolbarButtonContainerProps ) => (\n\t<div className={ className }>{ children }</div>\n);\n\nexport default ToolbarButtonContainer;\n"],"mappings":";AAAA;AACA;AACA;;AAGA,MAAMA,sBAAsB,GAAGA,CAAE;EAChCC,QAAQ;EACRC;AAC4B,CAAC,KAC7BC,aAAA;EAAKD,SAAS,EAAGA;AAAW,GAAGD,QAAe,CAC9C;AAED,eAAeD,sBAAsB"}

node_modules/@wordpress/components/build-module/toolbar/toolbar-button/toolbar-button-container.native.js

@@ -0,0 +1,7 @@
+import { createElement } from "react";
+/**
+ * External dependencies
+ */
+import { View } from 'react-native';
+export default (props => createElement(View, null, props.children));
+//# sourceMappingURL=toolbar-button-container.native.js.map

node_modules/@wordpress/components/build-module/toolbar/toolbar-button/toolbar-button-container.native.js.map

@@ -0,0 +1 @@
+{"version":3,"names":["View","props","createElement","children"],"sources":["@wordpress/components/src/toolbar/toolbar-button/toolbar-button-container.native.js"],"sourcesContent":["/**\n * External dependencies\n */\nimport { View } from 'react-native';\n\nexport default ( props ) => <View>{ props.children }</View>;\n"],"mappings":";AAAA;AACA;AACA;AACA,SAASA,IAAI,QAAQ,cAAc;AAEnC,gBAAiBC,KAAK,IAAMC,aAAA,CAACF,IAAI,QAAGC,KAAK,CAACE,QAAgB,CAAC"}

node_modules/@wordpress/components/build-module/toolbar/toolbar-button/types.js

@@ -0,0 +1,2 @@
+export {};
+//# sourceMappingURL=types.js.map

node_modules/@wordpress/components/build-module/toolbar/toolbar-button/types.js.map

@@ -0,0 +1 @@
+{"version":3,"names":[],"sources":["@wordpress/components/src/toolbar/toolbar-button/types.ts"],"sourcesContent":["/**\n * External dependencies\n */\nimport type { ReactNode } from 'react';\n\nexport type ToolbarButtonProps = {\n\t/**\n\t * Children to be rendered inside the button.\n\t */\n\tchildren?: ReactNode;\n\t/**\n\t * An optional class name for the button container.\n\t */\n\tcontainerClassName?: string;\n\t/**\n\t * Additional props to be passed alongside props.\n\t */\n\textraProps?: any;\n\t/**\n\t * Indicates if the button is active.\n\t */\n\tisActive?: boolean;\n\t/**\n\t * Indicates if the button is disabled.\n\t */\n\tisDisabled?: boolean;\n\t/**\n\t * An optional subscript for the button.\n\t */\n\tsubscript?: string;\n\t/**\n\t * An optional title/label for the button.\n\t */\n\ttitle?: string;\n};\n\nexport type ToolbarButtonContainerProps = {\n\t/**\n\t * Children to be rendered inside the button container.\n\t */\n\tchildren?: ReactNode;\n\t/**\n\t * An optional class name for the button container.\n\t */\n\tclassName?: string;\n};\n"],"mappings":""}