docs(row333 R2): fixtures section in BUILD.md, cause, production check, RED and GREEN counts (#1831)

agents/codex/work/queue-333/BUILD.md

@@ -31,3 +31,45 @@ Final implementation decisions and evidence:
 - Cleanup: original private mktemp root removed and absence verified; scoped runner EXIT trap removes its separate private root. All fixture servers/stores close through test cleanup. Mutant backup and temporary root marker removed. Isolated worktree retained for parent review; no production process, real proxy, account, config, credential path or provider was contacted.
 
 Limits and handoff: scoped GREEN is not the full landing gate. No package/full gates, Chromium/browser gates, acceptance binary, canonical queue mutation, remote issue post, push, merge or landing was run. Full/browser/combined gates remain with the parent under 1014.Q264 after admission; fresh independent Codex review is the parent's next task. No self-approval is claimed. Base remains 09a847eda and no unlanded662/657/658 feature bytes were imported.
+
+## R2 fixtures
+
+Base 09a847eda, row 333 tip ddb3e961f, R2 fixture commit 12eba4b59. Author: Claude (sub-agent of the Mosaic Stack lead, T3 c5c1e8ba). Issue #1831. No product code, business document schema or test assertion changed.
+
+Cause. Row 333 added packages/plugins/src/model-quota.mjs and imports it from packages/business/src/launch.mjs:3 and packages/business/src/organization.mjs:11. The cli release fixtures build smaller copies than a real stack copy: they copy packages/business/src and add only packages/plugins/src/kinds.mjs. Their business loader therefore failed with "Cannot find module .../packages/plugins/src/model-quota.mjs". Real copies are unaffected, because scripts/stack-copy.sh ships all of packages/plugins (COPY_PATHS, line 41). R1's evidence ran the 24 touched test files only (verify-scoped.sh, 174/174) and no package or cli gate, so it never built a release fixture copy and could not see this.
+
+Fixture changes (tests only):
+
+- packages/cli/tests/business-imports.mjs (new, 26 lines): businessImportedFiles(repo) reads the relative imports of every .mjs under packages/business/src and returns, sorted and repo-relative, the files outside that directory they reach, following those files' own imports. An import of a missing file throws. At this tip it returns packages/library/src/limits.mjs, mapping.mjs, problems.mjs, packages/plugins/src/kinds.mjs and packages/plugins/src/model-quota.mjs.
+- packages/cli/tests/stack-release-fixture.mjs:314 (copies for stack-release.test.mjs, stack-release-external.test.mjs and stack-upgrade.test.mjs): after the business, library and roles copy, copy each returned file that is not already in the copy. kinds.mjs is skipped on purpose, because the fixture has already written its KINDS_OLD or KINDS_NEW form there.
+- packages/cli/tests/stack-release.test.mjs:1994 (the RCOPIES copies): same loop.
+
+Searched for other fixtures that copy packages/business/src without the whole plugins directory: the grep over packages/*/tests, scripts and scripts/testing finds only those two. packages/cli/tests/case2-install.test.mjs:74 copies packages/business/src/vocabulary.mjs alone, which has no imports. stack-copy.test.mjs and stack-release-external.test.mjs:450 copy tracked files or the whole repository, so they carry model-quota.mjs already.
+
+Production check (every place that copies, mounts or packages business code or plugins/src/kinds.mjs without the whole plugins directory):
+
+- scripts/stack-copy.sh:32 copies packages/business/src and :41 copies the whole packages/plugins, so model-quota.mjs reaches every real copy. scripts/case2-install.sh:185 calls it.
+- scripts/stack-release.sh:371 and :378 import the copy's own packages/business/src/business.mjs, which reaches launch.mjs and so model-quota.mjs. That copy comes from stack-copy.sh, which takes both directories from the same commit.
+- packages/seat/src/sandbox.mjs RUNNER_FILES (:50-:72) mounts packages/business/src/vocabulary.mjs (:67) and packages/plugins/src/kinds.mjs (:68) only. A transitive import walk from all 19 listed files reaches no file of packages/business or packages/plugins outside that list; launch.mjs, organization.mjs, business.mjs, loader.mjs and model-quota.mjs are not reached. vocabulary.mjs and kinds.mjs import nothing. packages/seat/src imports only vocabulary.mjs from business (compactions.mjs:46, sandbox.mjs:40, session.mjs:42). model-quota.mjs is therefore not needed in the sandbox.
+- scripts/test-darkwing-launch.mjs:34 and scripts/test-rocko-launch.mjs:25 copy packages/seat/src alone, which needs only vocabulary.mjs.
+- Containerfile:23-26 copies contracts, src, two processing-control files and adapters; src imports nothing from packages. compose.yaml mounts the data root and the auth file only.
+- scripts/mosaic:35 and scripts/case2-precheck.sh:85,171 import business code from the repository or copy they sit in, which holds all of packages/plugins.
+
+Result: no production path misses model-quota.mjs. No product change was needed or made.
+
+RED, on ddb3e961f before the change (whole files, from packages/cli, one at a time, TMPDIR /mnt/storage/scratch/tmp/QYOMZY):
+
+- stack-release.test.mjs: 224 tests, 56 pass, 168 fail, 0 skip, 186 s. 127 log lines carry the missing-module message.
+- stack-release-external.test.mjs: 25 tests, 4 pass, 21 fail, 0 skip, 32 s.
+- stack-upgrade.test.mjs: 21 tests, 7 pass, 14 fail, 0 skip, 25 s.
+
+These match the counts the join child recorded (56/168, 4/21, 7/14).
+
+GREEN, on 12eba4b59:
+
+- stack-release.test.mjs: 224/224 pass, 0 fail, 0 skip, 694 s. stack-release-external.test.mjs: 25/25, 88 s. stack-upgrade.test.mjs: 21/21, 66 s.
+- cli whole (node --test tests/*.test.mjs): 1045 tests, 1044 pass, 0 fail, 1 skip, 656 s. The skip is "FED R7 scratch two-instance acceptance", which names scripts/test-federation-acceptance.sh as the way to run it.
+- business 286/286, 3 s. bus 1380/1380, 49 s. plugins 123/123, 1 s. model-proxy 108/108, 1.4 s. webui 492/492, 63 s. No skips in these. The model-final-completion.test.mjs:69 host flake (16 !== 19) did not appear, so no rerun was needed.
+- The counts for business (286) and plugins (123) are lower than the join's (292, 128) because the join included row 332's tests; this branch stays on base 09a847eda.
+
+Mutant. With the helper changed to drop model-quota.mjs from its result (a one-line filter in business-imports.mjs), stack-release.test.mjs gave 224 tests, 56 pass, 168 fail in 183 s, with 127 "Cannot find module .../packages/plugins/src/model-quota.mjs" lines. The helper then printed four files, without model-quota.mjs. git checkout restored the file; git status --short printed nothing afterwards.