docs(data-modeling): currency is a bare number in both modes; defaultCurrency is the column currency only under fixed (#20120)

Part of #20090

Clause-②: no

Docs half of the card: the two `content/docs/data-modeling` pages triage
named as the declared cross-domain surface (the card's item 1 and the
addendum). The `skills/**` half lands separately on
`claude/issue-20090-currency-mode-teaching` (Tier H, awaits human
approval); #20090 stays open until both have landed and the seat closes
it. Not a governed surface; no `meta.json` change (both pages already
exist).

## What changed

Text only, re-derived from the spec
(`packages/spec/src/data/field-value.zod.ts`: `currency` is in
`NUMERIC_VALUE_TYPES`, "`currency` IS a bare number"; `field.zod.ts`:
`currencyMode` `'dynamic' | 'fixed'` default `'dynamic'`,
`defaultCurrency` default `'CNY'`, and the guidance "a fixed currency is
declared as `currencyConfig: { currencyMode: 'fixed', defaultCurrency: …
}` … A field without one uses the tenant default at runtime"; the tenant
default's producer is the `localization.currency` setting in
`packages/services/service-settings/src/manifests/localization.manifest.ts`).

### `content/docs/data-modeling/field-types.mdx` (676 → 677 lines)

- The `currency` section's lead sentence now says the stored value is a
bare number in both modes and the currency code lives in
`currencyConfig`, never in the value.
- `currencyConfig.currencyMode` row: "Whether currency is per-record or
fixed" → "Whether the column is pinned to `defaultCurrency` (`fixed`) or
displays in the tenant default currency, the `localization.currency`
setting (`dynamic`); the value is a bare number either way".
- `currencyConfig.defaultCurrency` row: "Default currency code" → "The
column's currency code under `fixed`; not the displayed currency under
`dynamic`" (the row's own default is `'CNY'`, so the old description
read as "every dynamic column shows CNY").

### `content/docs/data-modeling/fields.mdx` (459 → 465 lines)

- The "Currency Configuration" example authored `currencyMode:
'dynamic', defaultCurrency: 'USD'` and never said USD is not the
displayed currency under `dynamic`. It now authors `'fixed'`, so the
`defaultCurrency` it shows is the currency it displays, with the two
modes explained in the comments.
- One short paragraph under the example states the rule: bare number in
both modes, never `{ value, currency }`; under `dynamic` (the default)
the amount displays in the tenant's `localization.currency` setting and
`defaultCurrency` is not the displayed currency; `fixed` pins the column
to `defaultCurrency`.

The generated reference `content/docs/references/data/field.mdx` is
untouched (auto-gen; its "dynamic (user selectable)" wording is the spec
describe's and is reported to the seat, not edited here).

## Changeset

`skip-changeset`: `content/docs/**` only — docs-only, nothing published
moves.

## Verification (head `c982ebfa`)

`node scripts/pm/dispatch-gates.mjs --commands --repo
objectstack-ai/objectstack` in this worktree, no paths, derives 40
families; every one run in the foreground with the exit captured before
any pipe, then reconciled: `--ran` verdict "40 derived, 40 run, 0
NOT-MEASURED, 0 UNRUN", exit 0. All 40 exit 0:

`check-ci-filter-parity` · `check-closing-keyword-parity` (+
`--self-test`) · `check-comment-mask-corpus` · `check-doc-frontmatter`
(+ `--self-test`) · `check-doc-route-spelling --advisory` (+
`--self-test`) · `check-docs-section-name` (+ `--self-test`) ·
`check-section-landing-index` (+ `--self-test`) · `@objectstack/lint
check:doc-formula-expressions` · `check:doc-security-posture` ·
`@objectstack/spec check:docs` (spec built first under the verify lock)
· `check:empty-state` · `check:liveness` · `check:skill-examples` ("259
prose examples type-check across 3 surface(s)") ·
`check:strictness-ledger` · `check:variant-docs` · `check:yaml-examples`
· `check:corpus-claim-drift` · `check:cross-package-test-inputs` ·
`check:doc-anchors` · `check:doc-authoring` · `check:docs-audit-scope` ·
`check:docs-redirects` · `check:docs-single-h1` ·
`check:docs-spec-enumerations` · `check:docs-transcript-drift` ·
`check:driver-memory-census` · `check:gitlink-declared` ·
`check:nul-bytes` · `check:published-readme-links` ·
`check:react-page-adapter-contract` · `check:refd-timer-probe` ·
`check:role-word` · `check:skill-identifier-liveness` ·
`check:vendor-version-stamps` · `check:watch-hint-literal`.

Prerequisite builds (`@objectstack/spec`, `@objectstack/formula` +
`@objectstack/lint`, `@objectstack/client-react` closure) ran under
`scripts/pm/os-verify-lock.sh`, each with `VERDICT command-exit 0`. No
reverse verification or ablation applies: prose with no consumer that
parses it.

## Acceptance notes

- `content/docs/api/data-api.mdx` calls the server-side resolution "the
ADR-0053 currency chain"; ADR-0053 is the date/datetime record and never
names currency. That page is outside this card's surface; #20091 (the
runtime half of the mode rule) remains open and is the carrier for the
chain and its comments. carrier: #20091.

---
_Generated by [Claude
Code](https://claude.ai/code/session_0148fenvVvyQV9HYxgVDQ33q)_

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

Author: objectstack-fleet[bot]

content/docs/data-modeling/field-types.mdx

@@ -143,7 +143,8 @@ Numeric value with optional precision.
 ```
 
 ### `currency`
-Monetary value with currency configuration.
+Monetary value. The stored value is a bare number in both modes; the currency
+code lives in `currencyConfig`, never in the value.
 
 | Property | Type | Default | Description |
 |:---|:---|:---|:---|
@@ -152,8 +153,8 @@ Monetary value with currency configuration.
 | `min` | `number` | — | Minimum value |
 | `max` | `number` | — | Maximum value |
 | `currencyConfig.precision` | `number` | `2` | Decimal precision for currency |
-| `currencyConfig.currencyMode` | `'dynamic' \| 'fixed'` | `'dynamic'` | Whether currency is per-record or fixed |
-| `currencyConfig.defaultCurrency` | `string` | `'CNY'` | Default currency code |
+| `currencyConfig.currencyMode` | `'dynamic' \| 'fixed'` | `'dynamic'` | Whether the column is pinned to `defaultCurrency` (`fixed`) or displays in the tenant default currency, the `localization.currency` setting (`dynamic`); the value is a bare number either way |
+| `currencyConfig.defaultCurrency` | `string` | `'CNY'` | The column's currency code under `fixed`; not the displayed currency under `dynamic` |
 
 ```typescript
 { name: 'price', label: 'Price', type: 'currency', currencyConfig: { precision: 2, currencyMode: 'fixed', defaultCurrency: 'USD' } }

content/docs/data-modeling/fields.mdx

@@ -74,12 +74,18 @@ price: Field.currency({
   label: 'Price',
   currencyConfig: {
     precision: 2,
-    currencyMode: 'dynamic',    // 'dynamic' | 'fixed'
-    defaultCurrency: 'USD',
+    currencyMode: 'fixed',      // 'fixed' pins the column to defaultCurrency;
+                                // 'dynamic' (default) shows the tenant default
+    defaultCurrency: 'USD',     // the column's currency under 'fixed'
   },
 }),
 ```
 
+The stored value is a bare number in both modes — never `{ value, currency }`.
+Under `dynamic` (the default) the amount displays in the tenant's
+`localization.currency` setting and `defaultCurrency` is not the displayed
+currency; `fixed` pins the column to `defaultCurrency`.
+
 ### Date & Time Types
 
 | Type | Factory | Description |