(; defense_gate_v2: accept / reject / INVESTIGATE)(; Usage: (if (== src verified) (if (> boost 0.20) reject (if (> boost 0.10) investigate accept)) reject))
(; Thresholds: low=0.10 mid=0.20 — gray zone triggers INVESTIGATE)
(; INVESTIGATE spawns: query-provenance, seek-corroboration, re-derive)
(; Verified 2026-04-24: boost>0.20=reject, 0.10-0.20=investigate, <0.10=accept)
(; INVESTIGATE protocol: (1) query-provenance source (2) seek-corroboration claim (3) re-derive from independent premises)