Enhance error resolution workflow and notification service

Refactored error log model and views to use a unified 'notes' field instead of 'resolution_notes'. Added a modal dialog for entering resolution notes when marking errors as resolved in admin views. Improved stack trace handling in ErrorHandler by storing as JSON and formatting for display. Expanded NotificationService to support multi-channel notifications (email, Telegram, Discord, Slack), group notifications, and improved domain expiration alerts.

app/Models/ErrorLog.php

@@ -350,7 +350,7 @@ class ErrorLog extends Model
             SET is_resolved = 1, 
                 resolved_at = NOW(), 
                 resolved_by = ?,
-                resolution_notes = ?
+                notes = ?
             WHERE error_id = ?
         ");
         
@@ -367,7 +367,7 @@ class ErrorLog extends Model
             SET is_resolved = 0, 
                 resolved_at = NULL, 
                 resolved_by = NULL,
-                resolution_notes = NULL
+                notes = NULL
             WHERE error_id = ?
         ");