servicedesk/src/app/Models/TriggerEmailTemplate.php

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Attributes\Fillable;
use Illuminate\Database\Eloquent\Model;

#[Fillable(['name', 'subject', 'body'])]
class TriggerEmailTemplate extends Model
{
    public function render(array $placeholders): array
    {
        $replace = function (string $text) use ($placeholders): string {
            foreach ($placeholders as $key => $value) {
                $text = str_replace('{'.$key.'}', (string) $value, $text);
            }

            return $text;
        };

        return [
            'subject' => $replace($this->subject),
            'body' => $replace($this->body),
        ];
    }
}