New clawhdf5-bench binary `search_harness`, the measurement baseline for the
search hot-path work. On deterministic clustered 384-dim data it reports HNSW
build time and, per ef, recall@10 against an exact scan, QPS and p50/p99; and
for HDF5Memory: ingest, checkpoint, open, first-query-after-open and
steady-state hybrid_search latency at 1K/10K (and 100K with --full). Optional
JSON output for tracking.
Baseline recorded in BENCHMARKS.md. It shows two problems: HNSW recall@10 does
not respond to ef and falls from 0.87 (1K) to 0.31 (100K) on clustered data,
and end-to-end hybrid_search is ~1000x slower than its vector stage because
every query rebuilds BM25 and rewrites the .h5 file.
Co-Authored-By: Claude Fable 5.1 <[email protected]>
