04 Writer Driver Builder

Verdict WRITER_DRIVER_BUILDER_LEGACY_RISK. Direct v5 repoint confirmed. Plan v5 is substantially copied v2 algorithm with fixed eligible statuses/strategy branches/full scan/apply_safe; writer trusts these before readiness. Writer still DEFAULT batch 1000. Driver relocates constants to unconstrained Directus-writable config, hardcodes keys, fallback 1. CURRENT plan uses LIMIT 1 without coherent-current invariant. Directus owns enforcement definitions.