Features:
- with_fast_memory(): Zero-latency inline extraction (Letta-style)
- Memory extracted as part of LLM response, no extra API calls
- Semantic retrieval with local embeddings (sub-50ms)
- with_memory(): Background extraction for non-blocking memory
- SQLite + FTS5 storage with vector similarity search
- Multi-user isolation by user_id
Memory enables temporal compression - extract key facts instead of
carrying full conversation history (4000 tokens → 50 tokens).
Includes:
- Comprehensive test suite (71 new tests)
- Documentation (docs/memory.md)
- Benchmark examples comparing approaches
- E2E test with LLM-as-judge evaluation
