refactor: use applesauce EventStore for offline event management

Major improvements:
- Store highlights in EventStore immediately when created
- Query EventStore instead of local relays for offline sync
- Pass eventStore to highlight creation service and hooks
- Simplified offline sync: no more relay queries, just EventStore lookups
- More efficient and reliable offline event tracking
- Better integration with applesauce architecture

Benefits:
- Faster sync (no relay queries needed)
- More reliable (events always in EventStore)
- Cleaner code (leveraging applesauce patterns)
- Better separation of concerns

src/components/Bookmarks.tsx

@@ -59,6 +59,7 @@ const Bookmarks: React.FC<BookmarksProps> = ({ relayPool, onLogout }) => {
   useOfflineSync({
     relayPool,
     account: activeAccount,
+    eventStore,
     relayStatuses,
     enabled: true
   })
@@ -129,6 +130,7 @@ const Bookmarks: React.FC<BookmarksProps> = ({ relayPool, onLogout }) => {
   } = useHighlightCreation({
     activeAccount,
     relayPool,
+    eventStore,
     currentArticle,
     selectedUrl,
     readerContent,