short_answer_de/en/se Felder + Distractor-Wörter in Fragen-Sidebar

- Directus: questions.short_answer_de/en/se Text-Felder angelegt
- Backend: short_answer_de beim Erstellen speichern
- Backend: get_object_questions_list gibt short_answer_de + distractor_words zurück
- Frontend: Sidebar zeigt Kurzantwort (blau) + Ablenker-Chips pro Frage

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/api.ts

@@ -235,6 +235,8 @@ export interface ObjectQuestion {
   id: string
   question_de: string
   answer_de: string
+  short_answer_de: string | null
+  distractor_words: string[]
   level: number
   status: string
 }