fix(spec): the two step-18 flow-binding D3 entries name only a text-slot hole and a CEL expression as the reads to rename (#23384)

Fixes #23338
Clause-②: no

Two ADR-0087 D3 semantic entries of protocol 18 still told an upgrading
author to rename "a single-brace token in a value position" among the
reads of a renamed variable. No protocol-18 value position reads a flow
variable through a single-brace token, so this PR takes the phrase out
of both `replacement` texts. It is a text-only change, following
triage's direction (comment 6155971636): the card's "Wanted", as
written.

Dispatched by the `domain:spec` seat 2 PM, session
`session_01BRQ9Mp1yH7R1az6MaUM18H`, under its claim comment 6159719865.

## What changes

-
`packages/spec/src/migrations/entries/semantic/18.flow-binding-name-dollar-refused.ts`
and `18.flow-binding-variable-dollar-name-refused.ts`: the last clause
of `replacement` names a text-slot hole and a CEL expression, and
nothing else. Each entry keeps its `id`, `fromVersion`, `toVersion`,
`surface`, `reason`, `acceptanceCriteria` and every other field
byte-identical. No schema, door, conversion or entry id changes.
- `.changeset/23338-flow-binding-d3-replacement-reads.md`: an
`@objectstack/spec` patch, with the FROM → TO sentence.

| FROM | TO |
|:--|:--|
| Rename every read of the old name with it — a text-slot hole, a CEL
expression, a single-brace token in a value position | Rename every read
of the old name with it — a text-slot hole, a CEL expression |

The new wording is the one PR #23252 gave both entries' changesets
(`22502` and `22572`, now under `.changeset/pre/`), and the one PR
#23336 put in the `18.0.0-next.0` entries of
`packages/spec/CHANGELOG.md`: "(a text-slot hole, a CEL expression)".
The generated upgrade guide and `spec-changes.json` now say the same as
those release notes.

Why it is true: S6 (`615c69604`) made every CRUD `filter` operand a
value slot, and S7 (`7958bdf36`) deleted the single-brace resolver. A
value slot takes a CEL value envelope or a literal, and a `{…}` token
there is refused. One measured nuance is stated in the changeset, so
that its sentence stays true: a CRUD `filter` operand that is one whole
query placeholder (`{current_user_id}`, `{today}`) is handed on to the
query engine untouched (the `filterOperand` arm of
`valueSlotTemplateRefusals`, judged by
`classifyFlowFilterOperandString`). That placeholder reads no flow
variable, so a renamed variable has no read there.

## The grep over every step-18 entry

At base `713f23185`, over `packages/spec/src/migrations/entries/**/18.*`
(769 files):

1. **The card's phrase**, `git grep -n "single-brace token in a value
position"` over the whole repository: exactly 2 hits, the two entries
above, and both are corrected here. At head `6bf205cb8` the only hit is
the FROM cell of this PR's changeset.
2. **The same idea in other words**, `git grep -n -i -E "single[-
]brace|value position|\{token\}|brace
token|\{var\}|single-curly|template dialect|template token"`: 22 hits in
9 entries. Apart from the two above, none reads the token as live:
- `18.flow-builtin-node-config-values-refused.ts` :40, :57, :86: a
`{token}` in a number or boolean slot is refused as the wrong type; at a
plain string key it parses and registers as a literal; `http`
interpolated "once" and "interpolates nothing now". No read is claimed.
- `18.flow-text-slot-single-brace-refused.ts` (5 hits): the text-slot
refusal.
- `18.flow-text-slot-unbound-dollar-root-refused.ts` :32, :35: "In 17.x
the slot was a plain string read by the single-brace interpolator", in
the past tense, and a refusal's remedy.
- `18.flow-value-slot-template-dialect-refused.ts` (4 hits): the
value-slot refusal, with the query-placeholder carve-out named.
- `18.flow-write-node-stored-metadata-target-refused.ts` :37: a
`{token}` `objectName` cannot be read as a name.
- `18.translation-flow-screen-title-text-slot-refused.ts` (4 hits): the
translated-heading refusal.
- `18.view-filter-rule-scalar-operator-array-refused.ts` :25: a filter
rule's "value position", which has nothing to do with templates.
3. **A third pass**, `brace` or `interpolat` outside the two spellings
above: 29 more hits in 13 entries. Each is in the past tense, a refusal,
or another dialect (`${…}` in UI action URLs, a datasource secret,
dashboard documents). None names a single-brace read as live.

The step-18 rationale fragments in `registry.ts.template` carry no such
sentence either. Their `single-brace` hits are refusals, plus the
statement that the single-brace interpolator is deleted.

## Generated projections and pins

- **No tracked file embeds the old sentence.** At base, `git grep
"Rename every read of the old name"` finds only the two entries.
`registry.ts`, `spec-changes.json` and the
`content/docs/protocol-upgrade/` pages are gitignored build output, so
nothing was regenerated or committed.
- **The projections carry the new text, measured on this head.**
`build-upgrade-guide.ts --out` and `build-spec-changes.ts --out` were
written to a scratch path. The old phrase has 0 hits in each (grep exit
1). The new sentence has 2 hits in the guide and 4 in
`spec-changes.json` (exit 0). In the built `dist/migrations/index.mjs`
and `index.js`, the old phrase is absent (exit 1) and the new sentence
has 2 hits each.
- **No test reads either `replacement` text.**
`flow-bound-variable-name.test.ts` pins only these two entries'
`surface`, `conversionIds` and rationale id, and `migrations.test.ts`
judges the shape of every semantic entry. No new test is added for a
text fix.

## Verification

All at head `6bf205cb8`, on base `713f23185`.

- `pnpm --filter @objectstack/spec build`, under the verify lock:
`VERDICT command-exit 0`.
- `pnpm --filter @objectstack/spec exec vitest run --maxWorkers=2
src/migrations src/automation/flow-bound-variable-name.test.ts`: 5
files, 323 tests passed.
- `pnpm --filter @objectstack/spec run typecheck` (`tsc --noEmit`,
`check:scripts-typecheck`, `check:test-typecheck`): exit 0.
- `pnpm turbo run build --filter=!@objectstack/docs --concurrency=2`,
under the lock: 75 successful, 75 total. This build is the prerequisite
of three derived gates.
- **Derived gates.** `node scripts/pm/dispatch-gates.mjs --commands
--repo objectstack-ai/objectstack`, with no paths, gives 82 commands.
Each ran with its exit code captured before any pipe.
- First pass: 79 exited 0. 3 exited 3 (`PREREQUISITE NOT MET`, nothing
built yet): `check:doc-formula-expressions`,
`check:dual-build-cjs-loads` and `check:lean-entry-closure`. After the
full build, all three exited 0.
- Among the 82, all exit 0: `check-adr-0087-registration`,
`check-empty-changeset`, `check-changeset-no-major`,
`check:upgrade-guide`, `check:spec-changes`, `check:authorable-surface`,
`check:doc-authoring` and `check:nul-bytes`.
- `--ran`: "82 derived famil(ies) accounted for — 82 run, 0 NOT-MEASURED
(a DERIVED zero — all 82 recorded an exit code and none of them is 3)."
- **ESLint, a measured narrowing.** `eslint --no-inline-config --format
json` over the 3 changed files. The 2 `.ts` files have 0 errors and 0
warnings. The config ignores the `.md` changeset. `eslint.config.mjs`
enables no type-aware linting (no `parserOptions.project`), so the diff
cannot move the verdict on an untouched file.
- **No consumer sweep.** Only string values change, so no export, type
or wire shape moves.

## Acceptance notes

- `origin/main` moved to `28e294f45` after the gates ran. Its one new
commit (plugin-sharing and runtime) touches neither entry and nothing in
`packages/spec`.

---
_Generated by [Claude
Code](https://claude.ai/code/session_01BRQ9Mp1yH7R1az6MaUM18H)_

Co-authored-by: Claude <noreply@anthropic.com>

Author: objectstack-fleet[bot]

.changeset/23338-flow-binding-d3-replacement-reads.md

@@ -0,0 +1,17 @@
+---
+'@objectstack/spec': patch
+---
+
+fix(spec): the two step-18 flow-binding D3 entries name only the reads a renamed variable has on protocol 18, a text-slot hole and a CEL expression
+
+Clause-②: no
+
+The `replacement` text of two ADR-0087 D3 semantic entries, `flow-binding-name-dollar-refused` and `flow-binding-variable-dollar-name-refused`, listed three ways a flow reads the old variable name, for the author to rename. Protocol 18 has only the first two. The protocol upgrade guide and `spec-changes.json` are generated from these entries, so they now say what the two entries' release notes already say.
+
+| FROM | TO |
+|:--|:--|
+| Rename every read of the old name with it — a text-slot hole, a CEL expression, a single-brace token in a value position | Rename every read of the old name with it — a text-slot hole, a CEL expression |
+
+No protocol-18 value position reads a flow variable through a single-brace `{…}` token. A value slot takes a CEL value envelope or a literal, and a `{…}` token there is refused. The one `{…}` string a value slot hands on is a CRUD `filter` operand's whole-string query placeholder (`{current_user_id}`, `{today}`): the query engine reads it, and it names no flow variable. A text slot reads `{{ }}` holes.
+
+Text only. No schema, door, conversion or entry id changes, and each entry keeps its `fromVersion`, `toVersion` and every other field.

packages/spec/src/migrations/entries/semantic/18.flow-binding-name-dollar-refused.ts

@@ -32,7 +32,7 @@ export const entry: SemanticMigration = {
     'the same name without the dollar sign, read as a hole over that name: iteratorVariable: \'row\' read as '
     + '{{ row.name }}, idVariable: \'account_id\' read as {{ account_id }}, a declared variable or an assignment '
     + 'target named total read as {{ total }}. Rename every read of the old name with it — a text-slot hole, a '
-    + 'CEL expression, a single-brace token in a value position',
+    + 'CEL expression',
   reason:
     'The dollar-named variables are the flow engine\'s own: it binds $record, $runId, $flowName, $flowLabel and '
     + '$error, a flat-graph loop binds $loopItems and $loopIndex, and a resume signal may not write any dollar '

packages/spec/src/migrations/entries/semantic/18.flow-binding-variable-dollar-name-refused.ts

@@ -25,7 +25,7 @@ export const entry: SemanticMigration = {
     'the same name without the dollar sign, read as a hole over that name: errorVariable: \'caught\' read as '
     + '{{ caught.message }}, outputVariable: \'lead\' read as {{ lead.name }}. A try_catch may instead drop '
     + 'errorVariable and read the engine\'s default, {{ $error.message }}. Rename every read of the old name '
-    + 'with it — a text-slot hole, a CEL expression, a single-brace token in a value position',
+    + 'with it — a text-slot hole, a CEL expression',
   reason:
     'The dollar-named variables are the flow engine\'s own: it binds $record, $runId, $flowName, $flowLabel and '
     + '$error, a flat-graph loop binds $loopItems and $loopIndex, and a resume signal may not write any dollar '