- Add getFeed method to FeedService
- Update FeedDetailScreen to use API instead of mock data
- Add loading and error states to FeedDetailScreen
- Replace loading UI with LoadingOverlay component (structured like PostDetailScreen)
- Add comment creation API types to feed.ts
- Add comment creation method to FeedService
- Implement comment creation in FeedDetailScreen (following PostDetailScreen pattern)
- Add comment list API types to feed.ts (if needed)
- Add comment list method to FeedService
- Update FeedDetailScreen to use comment API instead of mock data