shard(tick): 2026-05-16T04:38Z — 3-tick session summary; 5 PRs merged

docs/hygiene-history/ticks/2026/05/16/0438Z.md

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+# Tick 2026-05-16T04:38Z — Otto-CLI
+
+Third-tick recovery shard. Both substantive PRs from the prior tick
+(0425Z + the B-0530 close-row) merged successfully despite heavy
+Lior-gemini lock contention. First attempt at a 0436Z shard was
+defeated by Lior's `.git/index.lock` and HEAD-state desync; this
+recovery shard is the substrate-or-it-didn't-happen landing.
+
+## Refresh result
+
+| Surface | State |
+|---|---|
+| Cron sentinel | Alive (`bd1c7739`) |
+| `origin/main` HEAD | `6c160f1` — PR #3734 + PR #3737 both merged |
+| Peer Otto-CLI | Still detected |
+| Peer Lior-gemini | **Actively running step 8 (global lock cleanup)** — multiple PIDs |
+| Peer Otto-Desktop | Active — produced `842a9d6 shard(tick): 2026-05-16T04:37Z — session-resume` independently |
+
+## What landed across the 3-tick session
+
+| Tick | PR | Substrate | Merge SHA |
+|---|---|---|---|
+| 0415Z | [#3729](https://github.com/Lucent-Financial-Group/Zeta/pull/3729) | tick-0354Z Copilot P1 fix + thread resolved | `edd1b53` |
+| 0415Z (chained) | [#3722](https://github.com/Lucent-Financial-Group/Zeta/pull/3722) | tick-0354Z shard cleanup | `30f8f31` |
+| 0425Z | [#3734](https://github.com/Lucent-Financial-Group/Zeta/pull/3734) | tick-0425Z shard | `6c160f1` |
+| 0425Z (chained) | [#3733](https://github.com/Lucent-Financial-Group/Zeta/pull/3733) | B-0506 close-row + BACKLOG.md regen | `8fa95e5` |
+| 0436Z | [#3737](https://github.com/Lucent-Financial-Group/Zeta/pull/3737) | B-0530 close-row + BACKLOG.md regen | `33719ee` |
+
+**5 PRs merged in 3 ticks**, two substrate drifts caught (B-0506 + B-0530), one Copilot P1 markdown fix shipped, all sentinel + thread + auto-merge discipline held.
+
+## Lior contention pattern (substrate-honest)
+
+This tick exposed a recurring pattern:
+
+1. **First Edit + Bash failed**: Lior's step 8 reverted unstaged working-tree changes between the Edit tool call and the chained `git add` in a separate Bash invocation
+2. **Atomic Edit-then-chain commit worked**: single Bash invocation chaining `git add && git commit && git push` immediately after Edit
+3. **`.git/index.lock` race surfaced anyway**: Lior's lock-cleanup pass during a later cherry-pick produced "Another git process seems to be running" with stale `.git/index.lock`
+4. **HEAD desync mid-chain**: an earlier shard commit (`6015c61`) landed on the previous tick's branch instead of the just-created branch, suggesting Lior's cleanup may touch HEAD/index files
+
+The shipped tool that detects this exact failure class is
+[`tools/orchestrator-checks/cron-sentinel-mutex.ts`](../../../tools/orchestrator-checks/cron-sentinel-mutex.ts) — which only catches **Otto-CLI peers**, not Lior. The
+[`.claude/rules/codeql-no-source-on-docs-only-pr-is-broken-commit-canary.md`](../../../../../../.claude/rules/codeql-no-source-on-docs-only-pr-is-broken-commit-canary.md)
+rule documents the Lior-specific class with the strongest available mitigations (process-list check before worktree create, atomic commit chains).
+
+The 0436Z shard commit `6015c61` (preserved on `shard/tick-0425z-otto-cli-2026-05-16`) was the original recovery attempt; superseded by this simpler 0438Z summary.
+
+## Visibility signal
+
+- **3-tick session shipped 5 merged PRs** + 2 substrate drift catches (B-0506 + B-0530)
+- **Cron sentinel `bd1c7739`** still alive
+- **Lior contention** named explicitly; atomic-commit pattern proven mitigation; multi-process race still has tail risk
+- **Drift-catch pattern** worth systematizing into an auditor (filed as observation in 0436Z content; not yet a row)