feat(question): MCQ options authoring editor (Phase 2 domain foundation)

Backend now supports MCQ options + a separate answer-key table
(PUT /questions/:id/options). Frontend side of that, authoring only —
no candidate exam-taking UI.

- Question type gains options?: QuestionOption[] (no correctness field —
  the API never returns one, matching the backend's split-table design)
- New question-api hooks: getQuestionWithOptions, setQuestionOptions
- New QuestionOptionsEditor component (separate file, not inlined into
  QuestionPage) — add/remove/reorder options, mark correct, bilingual text
- Wired into the question edit form, shown only for an existing CHOICE
  question (options attach to an id, matching the backend's replace
  endpoint)
- en/am i18n strings for the new editor

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

apps/backoffice/src/app/features/question/api/question-api.ts

@@ -1,10 +1,12 @@
 import { baseApi } from '@ema-platform/api';
 import type {
   Question,
+  QuestionOption,
   ListResponse,
   CreateQuestionPayload,
   UpdateQuestionPayload,
   ReviewQuestionPayload,
+  SetQuestionOptionsPayload,
 } from '../types/question';
 
 const questionApi = baseApi.injectEndpoints({
@@ -17,6 +19,11 @@ const questionApi = baseApi.injectEndpoints({
       query: (id) => `/questions/${id}`,
       providesTags: ['Api'],
     }),
+    /** Same question, with `options` populated — the MCQ authoring editor. */
+    getQuestionWithOptions: builder.query<Question, string>({
+      query: (id) => `/questions/${id}?i=options`,
+      providesTags: ['Api'],
+    }),
     createQuestion: builder.mutation<Question, CreateQuestionPayload>({
       query: (body) => ({ url: '/questions', method: 'POST', body }),
       invalidatesTags: ['Api'],
@@ -47,6 +54,15 @@ const questionApi = baseApi.injectEndpoints({
       }),
       invalidatesTags: ['Api'],
     }),
+    /** Full replace of a CHOICE question's options + correct-answer set (Phase 2). */
+    setQuestionOptions: builder.mutation<QuestionOption[], SetQuestionOptionsPayload>({
+      query: ({ id, ...body }) => ({
+        url: `/questions/${id}/options`,
+        method: 'PUT',
+        body,
+      }),
+      invalidatesTags: ['Api'],
+    }),
   }),
   overrideExisting: false,
 });
@@ -54,9 +70,11 @@ const questionApi = baseApi.injectEndpoints({
 export const {
   useGetQuestionsQuery,
   useGetQuestionQuery,
+  useGetQuestionWithOptionsQuery,
   useCreateQuestionMutation,
   useUpdateQuestionMutation,
   useDeleteQuestionMutation,
   useSubmitQuestionMutation,
   useReviewQuestionMutation,
+  useSetQuestionOptionsMutation,
 } = questionApi;