feat(monitoring): add Laravel Nightwatch monitoring support

- Install laravel/nightwatch package for application monitoring
- Create Nightwatch console command to start the monitoring agent
- Add NIGHTWATCH_ENABLED and NIGHTWATCH_TOKEN environment variables
- Configure nightwatch settings in config/constants.php
- Set up Docker s6-overlay services for both development and production
- Disable Nightwatch by default in test environment

app/Console/Commands/Nightwatch.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace App\Console\Commands;
+
+use Illuminate\Console\Command;
+
+class Nightwatch extends Command
+{
+    protected $signature = 'start:nightwatch';
+
+    protected $description = 'Start Nightwatch';
+
+    public function handle(): void
+    {
+        if (config('constants.nightwatch.is_nightwatch_enabled')) {
+            $this->info('Nightwatch is enabled on this server.');
+            $this->call('nightwatch:agent');
+        }
+
+        exit(0);
+    }
+}