- Add useStoreTimeline hook for reactive EventStore queries
- Add dedupe helpers for highlights and writings
- Explore: seed highlights and writings from store instantly
- Article sidebar: seed article-specific highlights from store
- External URLs: seed URL-specific highlights from store
- Profile pages: seed other-profile highlights and writings from store
- Remove debug logging
- All data loads from cache first, then updates with fresh data
- Follows DRY principles with single reusable hook
