feat(admin-brand): add question expansion service and related functionality

- Implemented QuestionExpansionService for generating and materializing questions based on combinations and AI distillation.
- Added question metadata classification logic to infer intent and layer of questions.
- Created API handlers for question expansion operations including combination preview, AI distillation, metadata classification, and materialization.
- Introduced database migrations to support new question-related fields and constraints in brand_questions and brand_keywords tables.
- Added caching mechanism for AI distillation results to improve performance.
- Defined JSON schemas for question distillation responses to ensure data integrity.

apps/admin-web/src/router/index.ts

@@ -145,6 +145,16 @@ const router = createRouter({
             navKey: '/brands',
           },
         },
+        {
+          path: 'brands/:brandId/questions/create',
+          name: 'brand-question-create',
+          component: () => import('@/views/BrandQuestionCreateView.vue'),
+          meta: {
+            titleKey: 'route.brandQuestionCreate.title',
+            descriptionKey: 'route.brandQuestionCreate.description',
+            navKey: '/brands',
+          },
+        },
         {
           path: 'tracking',
           name: 'tracking',