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>

includes/Init.php

@@ -80,6 +80,18 @@ class Init {
     public function enqueue() {
         global $current_screen;
 
+        // Check coexistence mode - if React is active, don't load classic shared assets
+        $use_react = isset($_GET['react']) || get_option('formipay_use_react_admin', false);
+        $is_formipay_screen = strpos($current_screen->id, 'formipay') !== false;
+
+        // Don't load classic Grid.js/shared assets when React is active on admin pages
+        if ($use_react && $is_formipay_screen && $current_screen->base !== 'post') {
+            // Still load SweetAlert2 for React mode (needed for modals)
+            wp_enqueue_style( 'sweetalert2', FORMIPAY_URL . 'vendor/SweetAlert2/sweetalert2.min.css', [], '11.14.4', 'all');
+            wp_enqueue_script( 'sweetalert2', FORMIPAY_URL . 'vendor/SweetAlert2/sweetalert2.min.js', ['jquery'], '11.14.4', true);
+            return;
+        }
+
         $formipayCPTs = [
             'formipay-form' => __( 'Edit Form', 'formipay' ), 
             'formipay-product' => __( 'Edit Product', 'formipay' ),