shard(tick): 0027Z — multi-Otto contamination caught + side-worktree discipline

docs/hygiene-history/ticks/2026/05/15/0027Z.md

@@ -0,0 +1,38 @@
+# Tick 0027Z — multi-Otto contamination caught + side-worktree discipline applied
+
+## Headline
+
+Refresh detected primary-worktree HEAD on `shard/tick-0025Z-extraction-consolidation-otto-cli-2026-05-15` (a PARALLEL Otto's branch — PR [#3321](https://github.com/Lucent-Financial-Group/Zeta/pull/3321), opened ~10s before this tick fired by the parallel Otto in the same physical worktree). My active work is PR [#3320](https://github.com/Lucent-Financial-Group/Zeta/pull/3320) on `fix/sync-cited-memory-files-3312-2026-05-15`. Applied the worktree-force-remove-guard discipline: did NOT `git checkout` in the primary worktree (could clobber parallel Otto mid-edit); instead `git worktree add` at a fresh path `/tmp/zeta-otto-cli-0027z-sidetick`. This shard is written from that side worktree off the latest `origin/main`.
+
+## Collision risk identified
+
+Both parallel Otto's PR #3321 + my own PR #3320 introduce a `docs/hygiene-history/ticks/2026/05/15/0025Z.md` with **different content** for the same time slot:
+
+| PR | Branch | 0025Z.md scope |
+|---|---|---|
+| #3320 (mine) | `fix/sync-cited-memory-files-3312-2026-05-15` | PR #3312 merged + dead-pointer review-thread fix |
+| #3321 (parallel) | `shard/tick-0025Z-extraction-consolidation-otto-cli-2026-05-15` | Grok extraction attempt + partial preservation + CURRENT-files fast-path fix |
+
+Both have auto-merge armed; both green-or-near-green on required CI. Whichever merges first wins the file; the second hits a merge conflict and will need a rebase (rename to e.g. `0025Z-pr3320.md` or `0025Z-pr3321.md`).
+
+Not addressing the rename pre-emptively this tick — the conflict, when it surfaces, is bounded; the losing PR's owner Otto can rebase + rename cleanly. Pre-emptive rename in either PR risks doubling the conflict surface.
+
+## Discipline anchors
+
+- [`.claude/rules/zeta-expected-branch.md`](../../../../../.claude/rules/zeta-expected-branch.md) — field-test caveat: multi-Otto-one-checkout exposes the orchestrator-CWD-bleed-over hazard at a higher rate; the primary defense is `git branch --show-current` immediately before any commit
+- [`.claude/rules/claim-acquire-before-worktree-work.md`](../../../../../.claude/rules/claim-acquire-before-worktree-work.md) — worktree force-remove guard: "do NOT `git worktree remove --force` to take over peer Otto's worktree"; create a new worktree at a different path
+- [`.claude/rules/honor-those-that-came-before.md`](../../../../../.claude/rules/honor-those-that-came-before.md) — parallel Otto's work is legitimate; not competing for the worktree
+
+## Δ since 0025Z
+
+- Lior lane added [#3315](https://github.com/Lucent-Financial-Group/Zeta/pull/3315) (decompose-b0139-4), [#3316](https://github.com/Lucent-Financial-Group/Zeta/pull/3316) (shadow-log), [#3317](https://github.com/Lucent-Financial-Group/Zeta/pull/3317) (preserve-prs), [#3318](https://github.com/Lucent-Financial-Group/Zeta/pull/3318) (preserve), [#3319](https://github.com/Lucent-Financial-Group/Zeta/pull/3319) (shadow-vera). PR #3309 (decompose-b0139-3) merged at `5f42cd2`.
+- Parallel Otto opened [#3321](https://github.com/Lucent-Financial-Group/Zeta/pull/3321) at 00:27:18Z
+- PR #3320 (mine) sits at required 7/7 ok, auto-merge armed, very near auto-merge
+
+## Cron sentinel
+
+`c4ee20dd` still armed (every minute, `<<autonomous-loop>>`).
+
+## Next
+
+Cron-driven. Next tick verifies which of #3320 / #3321 merged first + which is now in conflict, then rebases the loser with file rename.