feat: add multi-tab fetching to news command for 5x more headlines

Completely rewrites the news command to fetch from multiple Explore tabs
(For You, News, Sports, Entertainment) using GenericTimelineById GraphQL
API instead of just the ExplorePage initialTimeline. This delivers 15+
AI-curated headlines instead of 3, a 5x improvement in content discovery.

Key Changes:
- Add GenericTimelineById query ID support with auto-refresh capability
- Implement multi-tab fetching with cross-tab headline deduplication
- Add CLI flags for granular tab filtering (--for-you, --news-only,
  --sports, --entertainment, --trending-only)
- Fetch from 4 tabs by default (excludes trending to reduce noise)
- Add early stopping optimization when count is reached
- Handle tab-level errors gracefully without failing entire request

Implementation:
- Added TIMELINE_IDS constant with base64 timeline identifiers
- Created fetchTimelineTab() method for GenericTimelineById requests
- Created parseTimelineTabItems() for new response structure
- Removed old parseNewsItems() and extractNewsItemsFromInstructions()
- Updated all 7 tests to mock GenericTimelineById responses

API Changes:
- NewsFetchOptions: Added `tabs?: ExploreTab[]` option
- ExploreTab type exported for library consumers
- Backward compatible - existing code continues to work

Documentation:
- Added comprehensive "News & Trending" section with examples
- Updated command reference with all new flags
- Added library usage examples with tab filtering
- Updated JSON schema documentation

Testing:
- All 268 tests passing
- Real-world verified: fetches 15+ AI headlines across tabs
- Tab filtering verified: --sports, --entertainment, etc all work

Co-Authored-By: Claude Sonnet 4.5 <[email protected]>

scripts/update-query-ids.ts

@@ -21,6 +21,7 @@ const TARGET_OPERATIONS = [
   'Likes',
   'ExploreSidebar',
   'ExplorePage',
+  'GenericTimelineById',
   'TrendHistory',
 ] as const;