docs(devlog): close the 260819 merge loop with its outcome record

devlog/_plan/260819_next_roadmap/070_next_roadmap_split_and_dogfood.md

@@ -4,6 +4,23 @@ Written 2026-08-19 after the queue-drain campaign closed. State at writing:
 56 open PRs (17 `review-ready`), 24 open `bug` issues, `dev` at `c4bf833c9`,
 npm `latest=2.26.0` / `preview=2.26.0-preview.20260819`.
 
+> **Status: stages A-C executed 2026-08-19.** 14 PRs merged including the full
+> split stack (#2019, #2023, #2036); 8 held with posted blockers. Outcome and
+> lessons: `090_merge_loop_outcome.md`. Per-phase evidence:
+> `080_merge_loop_ledger.md`.
+>
+> **What this document got wrong, again.** Its claim that a barrel extraction
+> cannot be meaningfully tested — and therefore needs the hygiene exception —
+> was disproved during execution. Forking a `Set` inside the barrel leaves
+> `tsc --noEmit` at exit 0, and no test imported the leaves directly, so barrel
+> and leaf were never compared to each other.
+> `tests/types-barrel-identity.test.ts` now covers it. Reuse the phase order
+> below; do not reuse the exception argument.
+>
+> **The preview soak gate (C3 and C5) has NOT run.** The split is on `dev` and
+> has never been exercised as a published build. That gate is still owed, and
+> the freeze-vs-shared-attribution question it raises is still a user decision.
+
 ## The question this answers
 
 Merging a mega-file split is not like merging a fix. A fix either works or

devlog/_plan/260819_next_roadmap/090_merge_loop_outcome.md

@@ -0,0 +1,86 @@
+# 090 — Merge-loop outcome
+
+HOTL loop, session `01a01949`, ten work-phases. **14 merged, 8 held.**
+
+## Merged
+
+| Work-phase | PRs |
+|---|---|
+| wp2 | #2085, #2086 |
+| wp3 | #2035, #2031, #1878 |
+| wp4 | #2103 |
+| wp5 | #1876 (closes #1852) |
+| wp6 | #2112, #1934, #2080 |
+| wp7-9 | #2019, #2023, #2036 — the split stack, bottom-up |
+| wp10 | #2119 — this loop's own two fixes |
+
+## Held, with posted blockers
+
+#2102, #2105, #2053, #2100, #2077, #2056, #2062, #2063 — all verified still
+OPEN at closeout. Nothing was swept in by a batch merge.
+
+## What the batching rule actually bought
+
+The user's instruction was to merge in small batches rather than sweeping
+stage 1 at once. Three defects were caught that a sweep would have shipped
+behind green CI:
+
+**#2105** — `reconcileShellHook(false)` unconditionally removes the hook, but
+`false` also means "`claude` is not on **this process's** `PATH`". A
+service-started proxy does not inherit the interactive login shell's `PATH`, so
+a user with Claude Code installed would have had their working `.zshrc` hook
+deleted. The change made the safe direction conditional and left the destructive
+one unconditional.
+
+**#1876** — the async catalog fix returned a pre-write `fresh` to a request that
+was already waiting when an invalidating write landed. `fresh` is the one state
+authorizing positive model guidance, so it would advertise a catalog the
+app-server no longer had. **A slow answer was the bug; a wrong answer is worse
+than the bug.** Fixed on our branch, and the existing regression had been
+asserting the defective `fresh` — the test was pinning the bug.
+
+**#2080** — a paid priority tier enabled from an assertion rather than evidence.
+Being wrong charges the user.
+
+## Three things this loop taught that outlive it
+
+**1. A verdict is bound to a head.** Every work-phase re-reviewed because heads
+had moved, and it mattered twice: #2102's author had changed the exact code the
+earlier verdict covered, and #2086's moved head added a `noVisionModels`
+precedence fix that was not in the reviewed diff.
+
+**2. Stale base is a claim about the base, not the change — four times over.**
+#2031 (60 behind), #1876 (67), #2019/#2023/#2036 (29). Each had red CI that went
+green on rebase with no source change. The converse stayed honest: a rebase
+removes the base as an explanation, it does not prove the change is good.
+
+**3. "No test is possible" was a claim, not a fact.** This document asserted
+across three campaigns that a barrel extraction's oracle is `tsc` plus its
+importers, and that a barrel test "restates the compiler". A review lane
+disproved it: forking `MODEL_ADAPTER_OVERRIDE_ALLOWED` into a second `Set`
+inside the barrel leaves `tsc --noEmit` at exit 0, and no test imported the
+leaves directly, so barrel and leaf were never compared. That test now exists
+(`tests/types-barrel-identity.test.ts`) and drives red against exactly that
+fork.
+
+The pattern across all three: **the conclusions held and the reasons did not.**
+Same finding as the previous campaign's closeout, arrived at independently.
+
+## A process failure worth recording
+
+wp6 held three PRs with three blockers. Two got follow-up fixes before merging;
+#2112's did not, and it landed with `codexToolMode` still absent from
+`providerConfigSchema`. Because that schema ends in `.passthrough()`, nothing
+failed — a misspelled value was accepted and silently resolved to the default.
+
+Caught at closeout and fixed (`d697e2553`), but the honest reading is that the
+hold did not hold. **A hold is worth exactly what the re-check before merge is
+worth**, and a passthrough schema leaves no trace at the merge boundary.
+
+## Still open
+
+- The 8 held PRs need author responses.
+- The preview/soak gate from `070` has not run. The split is on `dev`; it has
+  not been exercised as a published build.
+- `dev` CI on the final head was still in flight at closeout; no failing leg was
+  observed on any run in this loop.