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/svgo/plugins/removeNonInheritableGroupAttrs.js

@@ -0,0 +1,38 @@
+'use strict';
+
+const {
+  inheritableAttrs,
+  attrsGroups,
+  presentationNonInheritableGroupAttrs,
+} = require('./_collections');
+
+exports.name = 'removeNonInheritableGroupAttrs';
+exports.description =
+  'removes non-inheritable group’s presentational attributes';
+
+/**
+ * Remove non-inheritable group's "presentation" attributes.
+ *
+ * @author Kir Belevich
+ *
+ * @type {import('./plugins-types').Plugin<'removeNonInheritableGroupAttrs'>}
+ */
+exports.fn = () => {
+  return {
+    element: {
+      enter: (node) => {
+        if (node.name === 'g') {
+          for (const name of Object.keys(node.attributes)) {
+            if (
+              attrsGroups.presentation.has(name) &&
+              !inheritableAttrs.has(name) &&
+              !presentationNonInheritableGroupAttrs.has(name)
+            ) {
+              delete node.attributes[name];
+            }
+          }
+        }
+      },
+    },
+  };
+};