Replace the multi-round-trip while-loop in step 5.5 of recall_async with a
single WHERE chunk_id = ANY($1) query covering all candidate chunk IDs.
Token-budget accounting happens in Python after the single fetch.
Measured on a 97K-unit / 98M-link bank (budget=HIGH, include_chunks,
include_entities):
p50: 1.209s → 0.611s (−49%)
mean: 1.534s → 0.772s (−50%)
p95: 3.366s → 2.316s (−31%)
Also update recall_perf.py benchmark to use Budget.HIGH, include_chunks,
include_entities, and a realistic mixed fact_type distribution.
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