🔥 Remove Laravel Sail, Docker, and related setup, migrate to simplified local development environment

- **Removed:** `docker-compose.yml`, Sail-specific Dockerfiles, and related scripts for PHP 8.3 setup.
- **Updated:** Documentation to reflect a shift from Docker to a direct PHP-based local development workflow.
- **Removed:** `laravel/sail` dependency from `composer.lock`.
- **Implemented:** `#[Locked]` Livewire attribute across components for read-only properties.
- **Added:** Feature tests to ensure locked properties cannot be tampered with.

resources/views/livewire/courses/create-edit-events.blade.php

@@ -6,6 +6,7 @@ use App\Models\Course;
 use App\Models\CourseEvent;
 use App\Models\Venue;
 use App\Traits\SeoTrait;
+use Livewire\Attributes\Locked;
 use Livewire\Attributes\Validate;
 use Livewire\Component;
 
@@ -17,6 +18,7 @@ class extends Component {
     public Course $course;
     public ?CourseEvent $event = null;
 
+    #[Locked]
     public $country = 'de';
 
     public string $fromDate = '';