Add paper ranking by recency or citation signals #7
Description
Summary
Papers in the digest appear in feed order (newest first from each source). Add optional ranking by recency, citation count, or other impact signals.
Context
Some sources provide metadata beyond title/abstract — arXiv includes submission dates, Europe PMC includes citation counts. This data could be used to surface more impactful papers.
What to do
- Extend
SourcePreviewerparsers to extract date and citation count where available - Add a sort dropdown to the digest viewer (e.g., "Feed order", "Newest first", "Most cited")
- Implement sorting in the DigestViewer component before rendering
- Handle missing data gracefully (not all sources provide citations)
Considerations
- Sort should apply within each source section, not globally
- Citation data is only available from some sources (Europe PMC, potentially Semantic Scholar)
- Date-based sorting should work for all sources since most feeds are chronological