WhiteMagic memory — LMDB + Tantivy + LanceDB
Replaces the v2 SQLite + FTS5 + Python HNSW stack with:
- LMDB for key-value storage (mmap'd, zero-copy reads)
- Tantivy for full-text search (Rust, Lucene-class performance)
LanceDBfor vector similarity search (disk-based HNSW)