using a kebab options for deck tree node

api/src/services/flashcard-decks/destroy-service.ts

@@ -1,3 +1,4 @@
+import db from "@/db/db-client"
 import { FlashcardDeck } from "@/models"
 import BaseService from "@/services/base-service"
 
@@ -7,7 +8,13 @@ export class DestroyService extends BaseService {
   }
 
   async perform(): Promise<void> {
-    return this.flashcardDeck.destroy()
+    await db.transaction(async (transaction) => {
+      await FlashcardDeck.update(
+        { parentDeckId: null },
+        { where: { parentDeckId: this.flashcardDeck.id }, transaction }
+      )
+      await this.flashcardDeck.destroy({ transaction })
+    })
   }
 }