feat(cms): implement complete SysSiteCMS content management system

Initial implementation of the HomeSysPanel CMS built with Laravel 13.0.
Includes complete admin panel, content management, user authentication,
modular architecture for products/services/chatbot, and marketing tools.

Key features:
- User authentication with email verification and password reset
- Role-based access control (Admin/User with granular permissions)
- Content management (pages, news, FAQ, downloads, galleries, banners)
- Contact management system with subjects and responses
- Marketing tools (email campaigns, visitor analytics, social sharing)
- Modular architecture (Products, Services, Chatbot modules)
- AI Chatbot integration with OpenRouter.ai and LlamaCpp support
- Visitor tracking with geolocation
- SEO optimization with meta tags and Open Graph
- Responsive design with Bootstrap 5
- Dark mode support
- Maintenance mode
- Feature request system

app/Http/Controllers/Admin/ContactController.php

@@ -0,0 +1,52 @@
+<?php
+
+namespace App\Http\Controllers\Admin;
+
+use App\Http\Controllers\Controller;
+use App\Models\ContactMessage;
+use App\Models\ContactResponse;
+use App\Mail\ContactReplyMail;
+use Illuminate\Http\Request;
+use Illuminate\Support\Facades\Mail;
+use Illuminate\Support\Facades\Auth;
+
+class ContactController extends Controller
+{
+    public function index()
+    {
+        $contacts = ContactMessage::with('subject')->latest()->paginate(10);
+        return view('admin.contacts.index', compact('contacts'));
+    }
+
+    public function show(ContactMessage $contact)
+    {
+        $contact->update(['read' => true]);
+        $contact->load('responses.user', 'subject');
+        return view('admin.contacts.show', compact('contact'));
+    }
+
+    public function reply(Request $request, ContactMessage $contact)
+    {
+        $request->validate([
+            'message' => 'required|string|min:10',
+        ]);
+
+        // 1. Salvar no Banco de Dados
+        ContactResponse::create([
+            'contact_message_id' => $contact->id,
+            'user_id' => Auth::id(),
+            'message' => $request->message,
+        ]);
+
+        // 2. Enviar E-mail
+        Mail::to($contact->email)->send(new ContactReplyMail($contact, $request->message));
+
+        return redirect()->route('admin.contacts.show', $contact)->with('success', 'Resposta enviada e registrada com sucesso!');
+    }
+
+    public function destroy(ContactMessage $contact)
+    {
+        $contact->delete();
+        return redirect()->route('admin.contacts.index')->with('success', 'Mensagem excluída com sucesso.');
+    }
+}