feat(ST-zyb6qlnn): UserQuestions server-side ophalen en als prop doorzenden

- app/(app)/ideas/[id]/page.tsx: userQuestion.findMany + DTO-mapping
- components/ideas/idea-detail-layout.tsx: IdeaUserQuestionDto type +
  userQuestions prop toegevoegd aan Props interface en component-signature

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

components/ideas/idea-detail-layout.tsx

@@ -71,6 +71,14 @@ interface ProductOption {
   repo_url: string | null
 }
 
+export interface IdeaUserQuestionDto {
+  id: string
+  question: string
+  answer: string | null
+  status: 'pending' | 'answered'
+  created_at: string
+}
+
 interface Props {
   idea: IdeaDto
   grill_md: string | null
@@ -78,6 +86,7 @@ interface Props {
   products: ProductOption[]
   logs: IdeaLog[]
   questions: IdeaQuestion[]
+  userQuestions: IdeaUserQuestionDto[]
   isDemo: boolean
   initialTab: string
 }
@@ -89,6 +98,7 @@ export function IdeaDetailLayout({
   products,
   logs,
   questions,
+  userQuestions,
   isDemo,
   initialTab,
 }: Props) {