🔥 Add initial database migrations, seeders, and factories

🎨 Refactor `Lecturer` model to include new fields and factory usage
🔧 Update `DatabaseSeeder` to handle default seeds
🛠️ Enhance `einundzwanzig` database configuration for SQLite compatibility

app/Models/Category.php

@@ -2,11 +2,14 @@
 
 namespace App\Models;
 
+use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Eloquent\Relations\BelongsToMany;
 
 class Category extends Model
 {
+    use HasFactory;
+
     protected $connection = 'einundzwanzig';
 
     /** @var list<string> */