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/text/get-line-height.js

@@ -0,0 +1,36 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.getLineHeight = getLineHeight;
+var _space = require("../utils/space");
+var _utils = require("../utils");
+/**
+ * External dependencies
+ */
+
+/**
+ * Internal dependencies
+ */
+
+function getLineHeight(adjustLineHeightForInnerControls, lineHeight) {
+  if (lineHeight) return lineHeight;
+  if (!adjustLineHeightForInnerControls) return;
+  let value = `calc(${_utils.CONFIG.controlHeight} + ${(0, _space.space)(2)})`;
+  switch (adjustLineHeightForInnerControls) {
+    case 'large':
+      value = `calc(${_utils.CONFIG.controlHeightLarge} + ${(0, _space.space)(2)})`;
+      break;
+    case 'small':
+      value = `calc(${_utils.CONFIG.controlHeightSmall} + ${(0, _space.space)(2)})`;
+      break;
+    case 'xSmall':
+      value = `calc(${_utils.CONFIG.controlHeightXSmall} + ${(0, _space.space)(2)})`;
+      break;
+    default:
+      break;
+  }
+  return value;
+}
+//# sourceMappingURL=get-line-height.js.map