Add comprehensive queue management to browser phone shortcode

Features Added:
- Queue display showing all assigned queues for the current user
- Real-time queue statistics (waiting calls, capacity)
- Visual indicators for queues with waiting calls (green border, pulse animation)
- Queue selection with click interaction
- Accept next call from selected queue functionality
- Auto-refresh of queue data every 30 seconds
- Mobile-responsive queue interface

Backend Changes:
- New ajax_get_agent_queues() handler to fetch user's assigned queues
- Enhanced ajax_get_waiting_calls() to return structured data
- Proper permission checking for twp_access_agent_queue capability

Frontend Enhancements:
- Interactive queue list with selection states
- Queue controls panel showing selected queue info
- Refresh button for manual queue updates
- Visual feedback for queues with active calls
- Mobile-optimized layout for smaller screens

UI/UX Improvements:
- Queues with waiting calls highlighted with green accent
- Pulsing indicator for active queues
- Auto-selection of first queue with calls
- Responsive design for mobile devices
- Dark mode support for queue elements

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

admin/class-twp-admin.php

@@ -3973,7 +3973,47 @@ class TWP_Admin {
             ORDER BY c.position ASC
         ", $user_id));
         
-        wp_send_json_success($waiting_calls);
+        wp_send_json_success(array(
+            'count' => count($waiting_calls),
+            'calls' => $waiting_calls
+        ));
+    }
+    
+    /**
+     * AJAX handler for getting agent's assigned queues
+     */
+    public function ajax_get_agent_queues() {
+        // Check for either admin or frontend nonce
+        if (!$this->verify_ajax_nonce()) {
+            wp_send_json_error('Invalid nonce');
+            return;
+        }
+        
+        if (!current_user_can('manage_options') && !current_user_can('twp_access_agent_queue')) {
+            wp_send_json_error('Unauthorized - Agent queue access required');
+            return;
+        }
+        
+        global $wpdb;
+        $user_id = get_current_user_id();
+        $queues_table = $wpdb->prefix . 'twp_call_queues';
+        $groups_table = $wpdb->prefix . 'twp_group_members';
+        $calls_table = $wpdb->prefix . 'twp_queued_calls';
+        
+        // Get queues where user is a member of the assigned agent group
+        $user_queues = $wpdb->get_results($wpdb->prepare("
+            SELECT DISTINCT q.*, 
+                   COUNT(c.id) as waiting_count,
+                   COALESCE(SUM(CASE WHEN c.status = 'waiting' THEN 1 ELSE 0 END), 0) as current_waiting
+            FROM $queues_table q
+            LEFT JOIN $groups_table gm ON gm.group_id = q.agent_group_id
+            LEFT JOIN $calls_table c ON c.queue_id = q.id AND c.status = 'waiting'
+            WHERE gm.user_id = %d AND gm.is_active = 1
+            GROUP BY q.id
+            ORDER BY q.queue_name ASC
+        ", $user_id));
+        
+        wp_send_json_success($user_queues);
     }
     
     /**