Add comprehensive call control features and web phone transfer capabilities

## New Call Control Features
- Call hold/unhold with music playback
- Call transfer with agent selection dialog
- Call requeue to different queues
- Call recording with start/stop controls
- Real-time recording status tracking

## Enhanced Transfer System
- Transfer to agents with cell phones (direct)
- Transfer to web phone agents via personal queues
- Automatic queue creation for each user
- Real-time agent availability status
- Visual agent selection with status indicators (📱 phone, 💻 web)

## Call Recordings Management
- New database table for call recordings
- Recordings tab in voicemail interface
- Play/download recordings functionality
- Admin-only delete capability
- Integration with Twilio recording webhooks

## Agent Queue System
- Personal queues (agent_[user_id]) for web phone transfers
- Automatic polling for incoming transfers
- Transfer notifications with browser alerts
- Agent status tracking (available/busy/offline)

## Technical Enhancements
- 8 new AJAX endpoints for call controls
- Recording status webhooks
- Enhanced transfer dialogs with agent selection
- Improved error handling and user feedback
- Mobile-responsive call control interface

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

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

includes/class-twp-activator.php

@@ -44,7 +44,8 @@ class TWP_Activator {
             'twp_agent_groups',
             'twp_group_members',
             'twp_agent_status',
-            'twp_callbacks'
+            'twp_callbacks',
+            'twp_call_recordings'
         );
         
         $missing_tables = array();
@@ -284,6 +285,30 @@ class TWP_Activator {
             KEY queue_id (queue_id)
         ) $charset_collate;";
         
+        // Call recordings table
+        $table_recordings = $wpdb->prefix . 'twp_call_recordings';
+        $sql_recordings = "CREATE TABLE $table_recordings (
+            id int(11) NOT NULL AUTO_INCREMENT,
+            call_sid varchar(100) NOT NULL,
+            recording_sid varchar(100),
+            recording_url varchar(500),
+            duration int(11) DEFAULT 0,
+            from_number varchar(20),
+            to_number varchar(20),
+            agent_id bigint(20),
+            status varchar(20) DEFAULT 'recording',
+            started_at datetime DEFAULT CURRENT_TIMESTAMP,
+            ended_at datetime,
+            file_size int(11),
+            transcription text,
+            notes text,
+            PRIMARY KEY (id),
+            KEY call_sid (call_sid),
+            KEY recording_sid (recording_sid),
+            KEY agent_id (agent_id),
+            KEY started_at (started_at)
+        ) $charset_collate;";
+        
         dbDelta($sql_schedules);
         dbDelta($sql_queues);
         dbDelta($sql_queued_calls);
@@ -296,6 +321,7 @@ class TWP_Activator {
         dbDelta($sql_group_members);
         dbDelta($sql_agent_status);
         dbDelta($sql_callbacks);
+        dbDelta($sql_recordings);
         
         // Add missing columns for existing installations
         self::add_missing_columns();