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+| 2026-04-30T23:30:00Z | opus-4-7 / session continuation | 1d1f226 | Generative-tooling tick. Built tools/hygiene/check-tick-history-shard-schema.sh — write-time schema validator for per-tick shards. Catches the col1 parenthetical drift that propagated across 15+ shards over 3 days before Copilot caught it. Three rules enforced: (1) filename matches HHMMZ.md or HHMMSSZ-<hash>.md per schema; (2) first line opens with `| YYYY-MM-DDTHH:MM(:SS)?Z |` exactly (both ISO forms accepted); (3) col1 timestamp date + HH:MM matches filename path. Lands in DORMANT mode (not yet wired into CI/pre-push) because 5 April-28 shards on main still violate it AND those 5 are implicated in the prefab finding (#973) — mechanical fix would launder the body-level prefab claim. Will go binding after prefab-vs-schema decision lands. Composes with B-0114 sub-item 1 (pre-push lint hook) + #969 rediscoverable-from-main invariant. PR #975 armed. | #975 (armed) | Observation — this is the structural-fix-beats-process-discipline pattern (Otto-341) applied to the tick-history surface. Two days ago the col1 violation propagated via copy-from-prior-shard because each tick author looked at the most recent shard, copied the format, and inherited the defect. The check makes the propagation visible at write-time. The DORMANT-mode landing is also load-bearing: a binding check that 5 known-good-content shards fail would create CI-bypass pressure (the worst kind of process-vs-substrate trade). Better to land the tool, document the known-stale set, and let the maintainer decide cleanup order. |