Major changes:
- Replace OOM-causing in-memory BM25 with PostgreSQL full-text search
- Add tsvector column and GIN index for fast keyword search
- Implement hybrid score fusion (70% embedding + 30% FTS + 15% bonus)
- Add CANDIDATE_MULTIPLIER (5x) to search more candidates before fusion
- Add stopword filtering to FTS queries for less strict matching
- Make search limit configurable (default 20, max 100)
- Propagate relevance scores through the search pipeline
Search improvements:
- "clowns iconoclasts" → finds target at rank 1 (score 0.815)
- "replacing words with definitions" → finds target at rank 1
- Vague queries now find results with limit=30 that were previously missed
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
