Update Zetian example imports for accuracy

Revised the import statements in all example code snippets to use the correct Zetian namespaces and classes. This ensures the examples reflect the current Zetian API structure and improve clarity for users referencing these code samples.

Author: Taiizor

.pages/app/examples/page.tsx

@@ -21,7 +21,7 @@ const examples = [
     icon: Zap,
     color: 'from-blue-500 to-indigo-600',
     difficulty: 'Beginner',
-    code: `using Zetian;
+    code: `using Zetian.Server;
 
 // Basic SMTP server - accepts all messages
 using var server = new SmtpServerBuilder()
@@ -49,8 +49,8 @@ Console.WriteLine("SMTP Server is running on port 25");`
     icon: Shield,
     color: 'from-green-500 to-emerald-600',
     difficulty: 'Intermediate',
-    code: `using Zetian;
-using Zetian.Authentication;
+    code: `using Zetian.Models;
+using Zetian.Server;
 
 // Authenticated SMTP server
 using var server = new SmtpServerBuilder()
@@ -93,8 +93,7 @@ Console.WriteLine("SMTP Server with authentication on port 587");`
     icon: Lock,
     color: 'from-purple-500 to-pink-600',
     difficulty: 'Intermediate',
-    code: `using Zetian;
-using Zetian.Authentication;
+    code: `using Zetian.Server;
 
 // Secure SMTP server with TLS/SSL support
 using var server = new SmtpServerBuilder()
@@ -127,8 +126,9 @@ Console.WriteLine("Secure SMTP Server running with STARTTLS support on port 587"
     icon: Gauge,
     color: 'from-yellow-500 to-orange-600',
     difficulty: 'Intermediate',
-    code: `using Zetian.Extensions;
-using Zetian.Extensions.RateLimiting;
+    code: `using Zetian.Models;
+using Zetian.Server;
+using Zetian.Extensions;
 
 // SMTP server protected with rate limiting
 using var server = new SmtpServerBuilder()
@@ -165,7 +165,8 @@ Console.WriteLine("Rate-limited server on port 25");`
     icon: Filter,
     color: 'from-red-500 to-rose-600',
     difficulty: 'Advanced',
-    code: `using Zetian;
+    code: `using Zetian.Server;
+using Zetian.Protocol;
 
 // Protocol-level filtering
 using var server = new SmtpServerBuilder()
@@ -211,9 +212,10 @@ await server.StartAsync();`
     icon: Database,
     color: 'from-teal-500 to-cyan-600',
     difficulty: 'Advanced',
-    code: `using Zetian;
-using Zetian.Storage;
+    code: `using System.Net;
+using Zetian.Server;
 using System.Text.Json;
+using Zetian.Abstractions;
 
 // SMTP server with built-in file storage
 using var server = new SmtpServerBuilder()