Various code cleanup.

app/Models/Attachment.php

@@ -66,14 +66,16 @@ class Attachment extends Model
             'deleted_at' => 'datetime',
             'uploaded'   => 'boolean',
         ];
-    /** @var array */
+    /** @var array Fields that can be filled */
     protected $fillable = ['attachable_id', 'attachable_type', 'user_id', 'md5', 'filename', 'mime', 'title', 'description', 'size', 'uploaded'];
 
     /**
+     * Route binder. Converts the key in the URL to the specified object (or throw 404).
+     *
      * @param string $value
      *
      * @return Attachment
-     * @throws \Symfony\Component\HttpKernel\Exception\NotFoundHttpException
+     * @throws NotFoundHttpException
      */
     public static function routeBinder(string $value): Attachment
     {