fix(types): add attachments to CreateNotificationDTO type (medusajs#12936)

Closes medusajs#12702

Author: shahednasser

.changeset/gorgeous-beers-travel.md

@@ -0,0 +1,5 @@
+---
+"@medusajs/types": patch
+---
+
+fix(types): add attachments to CreateNotificationDTO type

packages/core/types/src/notification/mutations.ts

@@ -1,4 +1,4 @@
-import { NotificationContent } from "./common"
+import { Attachment, NotificationContent } from "./common"
 
 /**
  * @interface
@@ -52,4 +52,8 @@ export interface CreateNotificationDTO {
    * An idempotency key that ensures the same notification is not sent multiple times.
    */
   idempotency_key?: string | null
+  /**
+   * Optional attachments for the notification.
+   */
+  attachments?: Attachment[] | null
 }