Fix browser phone permission issues for phone agents

- Fixed error message display when browser phone initialization fails (now shows actual error instead of "undefined")
- Fixed ajax_get_phone_numbers to use wp_send_json_error instead of wp_die for proper error handling
- Added error handling for phone numbers loading in browser phone interface
- Updated phone_agent role to ensure all necessary capabilities are added to existing roles
- Added automatic capability updates for existing phone_agent roles on plugin load

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

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

admin/class-twp-admin.php

@@ -2976,7 +2976,8 @@ class TWP_Admin {
         check_ajax_referer('twp_ajax_nonce', 'nonce');
         
         if (!current_user_can('manage_options') && !current_user_can('twp_access_phone_numbers')) {
-            wp_die('Unauthorized');
+            wp_send_json_error('Unauthorized - Phone number access required');
+            return;
         }
         
         $twilio = new TWP_Twilio_API();
@@ -5508,7 +5509,9 @@ class TWP_Admin {
                                 $('#browser-phone-error').hide();
                                 setupTwilioDevice(response.data.token);
                             } else {
-                                showError('Failed to initialize: ' + response.error);
+                                // WordPress wp_send_json_error sends the error message as response.data
+                                var errorMsg = response.data || response.error || 'Unknown error';
+                                showError('Failed to initialize: ' + errorMsg);
                             }
                         }).fail(function() {
                             showError('Failed to connect to server');
@@ -5690,7 +5693,13 @@ class TWP_Admin {
                             options += '<option value="' + number.phone_number + '">' + number.phone_number + '</option>';
                         });
                         $('#caller-id-select').html(options);
+                    } else {
+                        console.error('Failed to load phone numbers:', response.data || response.error);
+                        $('#caller-id-select').html('<option value="">Error loading numbers</option>');
                     }
+                }).fail(function(xhr, status, error) {
+                    console.error('Failed to load phone numbers - network error:', error);
+                    $('#caller-id-select').html('<option value="">Error loading numbers</option>');
                 });
                 
                 // Dialpad functionality

includes/class-twp-core.php

@@ -89,8 +89,20 @@ class TWP_Core {
             ));
         } else {
             // Update existing role with any missing capabilities
-            if (!$role->has_cap('twp_access_phone_numbers')) {
-                $role->add_cap('twp_access_phone_numbers');
+            $capabilities = array(
+                'twp_access_voicemails',
+                'twp_access_call_log',
+                'twp_access_agent_queue',
+                'twp_access_outbound_calls',
+                'twp_access_sms_inbox',
+                'twp_access_browser_phone',
+                'twp_access_phone_numbers'
+            );
+            
+            foreach ($capabilities as $cap) {
+                if (!$role->has_cap($cap)) {
+                    $role->add_cap($cap);
+                }
             }
         }
     }