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/stylelint/lib/formatters/index.js

@@ -0,0 +1,16 @@
+'use strict';
+
+const importLazy = require('import-lazy');
+
+/** @type {typeof import('stylelint').formatters} */
+const formatters = {
+	compact: importLazy(() => require('./compactFormatter'))(),
+	github: importLazy(() => require('./githubFormatter'))(),
+	json: importLazy(() => require('./jsonFormatter'))(),
+	string: importLazy(() => require('./stringFormatter'))(),
+	tap: importLazy(() => require('./tapFormatter'))(),
+	unix: importLazy(() => require('./unixFormatter'))(),
+	verbose: importLazy(() => require('./verboseFormatter'))(),
+};
+
+module.exports = formatters;