feat(attachments): add AttachmentType enum and update Attachment model to use it

app/Domains/Attachable/Enums/AttachmentType.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace App\Domains\Attachable\Enums;
+
+enum AttachmentType: string
+{
+    case Image = 'image';
+    case Video = 'video';
+    case Pdf = 'pdf';
+    case Document = 'document';
+    case Audio = 'audio';
+    case Other = 'other';
+}

app/Domains/Attachable/Models/Attachment.php

@@ -2,6 +2,7 @@
 
 namespace App\Domains\Attachable\Models;
 
+use App\Domains\Attachable\Enums\AttachmentType;
 use Illuminate\Database\Eloquent\Attributes\Fillable;
 use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Model;
@@ -35,6 +36,7 @@ class Attachment extends Model
     {
         return [
             'attachable_id' => 'integer',
+            'type' => AttachmentType::class,
             'size' => 'integer',
         ];
     }