fix(m12): IdeaTimeline auto-refresh on new idea-questions

The /ideas/[id]?tab=timeline page is server-rendered: questions are a
prop snapshot. Without a router.refresh, new questions only show after a
manual page reload — and during a grill-session that's every ~20s.

Fix: in use-notifications-realtime, after dispatching idea-question
events to idea-store + re-syncing the bell, call \`router.refresh()\`.
This re-runs the server-component for whichever page the user is on; on
/ideas/[id] it pulls the new question. On other pages it's a no-op (no
visible state change).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

lib/realtime/use-notifications-realtime.ts

@@ -11,6 +11,7 @@
 'use client'
 
 import { useEffect, useRef } from 'react'
+import { useRouter } from 'next/navigation'
 import { useNotificationsStore, type NotificationQuestion } from '@/stores/notifications-store'
 import { useIdeaStore } from '@/stores/idea-store'
 
@@ -66,6 +67,7 @@ export function useNotificationsRealtime() {
   const sourceRef = useRef<EventSource | null>(null)
   const backoffRef = useRef<number>(BACKOFF_START_MS)
   const reconnectTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null)
+  const router = useRouter()
 
   useEffect(() => {
     const init = useNotificationsStore.getState().init
@@ -146,6 +148,11 @@ export function useNotificationsRealtime() {
             } else {
               remove(payload.id)
             }
+            // M12 hotfix: refresh de current page (server-component) zodat de
+            // IdeaTimeline-tab op /ideas/[id] de nieuwe vraag oppikt zonder
+            // dat de gebruiker handmatig moet refreshen. Geen-op als de
+            // gebruiker elders zit; goedkoop genoeg om altijd te triggeren.
+            router.refresh()
             return
           }