(; Artifact 26: Staleness Purge — time-based confidence decay for uncorroborated beliefs)(; Design: each belief tagged with last_corroborated_cycle. If current_cycle - last_corroborated > 30 AND zero revision events in window, apply conf *= 0.9^(cycles_since - 30))
(; Key insight from g71: revision-as-decay FAILS because NAL revision conf monotonically rises with evidence. Staleness MUST use explicit time-discount OUTSIDE revision system.)
(; SCENARIO: belief (--> old_server reliable) stv 0.8 0.7 last corroborated cycle 15. Current cycle 50. Cycles since=35, stale by 5. Decay: 0.7 * 0.9^5 = 0.413. Still active. By cycle 60: 0.7 * 0.9^25 = 0.053 → auto-archive.)
(; AUTO-ARCHIVE RULE: if decayed_conf < 0.3 → move belief to archive-space with tag (archived stale cycle_N original_stv). Recoverable: new corroborating evidence triggers unarchive + revision with fresh timestamp.)
(; Integration: staleness sweep every 10 cycles, runs AFTER art25 drift check, BEFORE art19 gate. Order: art25(drift)→art26(staleness)→art19(defense gate). Stale beliefs cannot anchor drift detection — art25 skips beliefs already flagged stale.)
(; Critical interaction: art26 staleness + art25 drift are COMPLEMENTARY — drift catches beliefs resistant to counter-evidence, staleness catches beliefs with NO evidence flow at all. Together they cover the full neglect spectrum.)