fix: Add SPA mounting point for full mode

Problem: Customer SPA not loading in 'full' mode
Root Cause: In full mode, SPA loads on WooCommerce pages without shortcodes, so there's no #woonoow-customer-app div for React to mount to

Solution: Inject mounting point div when in full mode via woocommerce_before_main_content hook

Changes:
- Added inject_spa_mount_point() method
- Hooks into woocommerce_before_main_content when in full mode
- Only injects if mount point doesn't exist from shortcode

Result:
✅ Full mode now has mounting point on WooCommerce pages
✅ Shortcode mode still works with shortcode-provided divs
✅ Customer SPA can now initialize properly

includes/Frontend/Assets.php

@@ -15,6 +15,7 @@ class Assets {
         add_action('wp_head', [self::class, 'add_inline_config'], 5);
         add_action('wp_enqueue_scripts', [self::class, 'dequeue_conflicting_scripts'], 100);
         add_filter('script_loader_tag', [self::class, 'add_module_type'], 10, 3);
+        add_action('woocommerce_before_main_content', [self::class, 'inject_spa_mount_point'], 5);
     }
     
     /**
@@ -113,6 +114,24 @@ class Assets {
         }
     }
     
+    /**
+     * Inject SPA mounting point for full mode
+     */
+    public static function inject_spa_mount_point() {
+        if (!self::should_load_assets()) {
+            return;
+        }
+        
+        // Check if we're in full mode and not on a page with shortcode
+        $spa_settings = get_option('woonoow_customer_spa_settings', []);
+        $mode = isset($spa_settings['mode']) ? $spa_settings['mode'] : 'disabled';
+        
+        if ($mode === 'full') {
+            // Only inject if the mount point doesn't already exist (from shortcode)
+            echo '<div id="woonoow-customer-app" data-page="shop"><div class="woonoow-loading"><p>Loading...</p></div></div>';
+        }
+    }
+    
     /**
      * Add inline config and scripts to page head
      */