fix(spec): drop the tabs alias on a page component translation entry; the docs table names the tab-item key

The alias put a `tabs` key beside `emptyState` in one object literal,
which the list-view tabs retirement's tree-scoped absence pin reads as a
list-view payload carrying `tabs` (translation.zod.ts:1191). The alias was
not part of the card's ask, so it goes rather than widening the pin's
exclusions. content/docs/ui/translations.mdx gains the
pages.NAME.components.TABS.items.VALUE.label row.

Co-authored-by: Claude <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D6F9axfoPzR7t8G1J7Ytzz

Author: claude

.changeset/24968-page-tabs-item-label-key.md

@@ -9,7 +9,7 @@ feat(spec): a `page:tabs` item label gains a translation key, `pages.<page>.comp
 Clause-②: yes (widening)
 
 - **Before.** `pages.<page>.components` is keyed by component id, and a `page:tabs` item is not a component and carries no id, so a tab label had no key. `items` was refused as an unknown key, and `translatePage` never read `items[].label`. A localized page kept its tab strip in the authoring language.
-- **Now.** `pages.<page>.components.<tabsId>.items.<value>.label` is a declared key. It is addressed by the tabs component's own `id` and the item's `value` (the stable `?tab=` token), and `translatePage` overlays it onto that item's `label`, across the locale chain. The entry is closed: `title`, `name` and `text` are renames onto `label`, and `tabs` on a component entry is the rename onto `items`. An item without a `value` has no key, because its renderer token is index-derived and an array index is never a bundle key. Author a `value` on the item, or keep localizing that label with an inline locale map.
+- **Now.** `pages.<page>.components.<tabsId>.items.<value>.label` is a declared key. It is addressed by the tabs component's own `id` and the item's `value` (the stable `?tab=` token), and `translatePage` overlays it onto that item's `label`, across the locale chain. The entry is closed: `title`, `name` and `text` are renames onto `label`. An item without a `value` has no key, because its renderer token is index-derived and an array index is never a bundle key. Author a `value` on the item, or keep localizing that label with an inline locale map.
 - **`walkAddressedPageComponents`.** A visitor's edit to a panel's own keys (its `label`) now stands when the visitor keeps the panel list's authored shape. Panel children are still descended from the authored document.
 - **`objectstack validate`.** `@objectstack/lint`'s translation-reference check accepts the key over a declared `page:tabs` item `value`. It refuses it as `translation-target-unknown` over an unknown value (with "Did you mean"), over a component of another type (a `page:accordion` is pointed at the inline locale map, since its panels have no stable key), and under a component id the page does not declare.
 - **`os i18n extract` / coverage.** The extractor writes a slot for every valued tab item, and the coverage check demands it. An inline locale map on the item label is counted as authored, as before.

content/docs/ui/translations.mdx

@@ -80,6 +80,7 @@ export default defineStack({
 | Dataset dimension and measure labels | `datasets.<name>.dimensions.<dimension>.label` / `datasets.<name>.measures.<measure>.label` |
 | Page labels and `page:header` copy | `pages.<name>.label` / `description` / `title` / `subtitle` — on a `kind: 'slotted'` page the header under `slots.header` is the page's header |
 | Page component copy, by component id | `pages.<name>.components.<id>.title` / `description` / `label` / `placeholder` / `emptyText` — reached under `regions[].components[]` and `slots.<slot>`, through `properties.children` and a `page:tabs` / `page:accordion` panel's `items[].children` |
+| Page tab labels (`page:tabs` items) | `pages.<name>.components.<tabsId>.items.<value>.label` — keyed by the tabs component's `id` and the item's `value`; an item without a `value` has no key (localize it with an inline locale map), and `page:accordion` panels have none |
 | Screen-flow wizards (flow label, screen headings and body text, screen field copy) | `flows.<flow>.label` / `flows.<flow>.screens.<node_id>.title` / `.description` / `.fields.<field>.label` / `.placeholder` / `.inlineHelpText` — a screen field's help text is `inlineHelpText`, the key the field itself declares, not `help`; see the boundary note below |
 | Global actions, messages | `globalActions`, `messages` |
 | Settings UI shell copy (the source badge on a settings row) | `settingsCommon.sourceLabels.<layer>` — the per-namespace settings copy under `settings` is **platform-only**: an app bundle carrying it is refused by name, and the platform's own strings are translated in `@objectstack/service-settings`'s bundle |

packages/spec/src/system/translation.test.ts

@@ -1007,12 +1007,6 @@ describe('translation unknown-key strictness', () => {
       expect(result.error?.issues.find((i) => i.code === 'unrecognized_keys')?.message).toContain('`title` → `label`');
     });
 
-    it('names `tabs` on a component entry as the rename onto `items`', () => {
-      const result = parse({ home_tabs: { tabs: { my_leads: { label: 'My Leads' } } } });
-      expect(result.success).toBe(false);
-      expect(result.error?.issues.find((i) => i.code === 'unrecognized_keys')?.message).toContain('`tabs` → `items`');
-    });
-
     it('carries the `label`/`title` trap alias the dashboard widget face carries', () => {
       // A page's headline is `label`; a component's is `title`. One level
       // apart, opposite spellings — the same trap `dashboards.widgets` names.

packages/spec/src/system/translation.zod.ts

@@ -1188,7 +1188,7 @@ const appTranslationDataShape = () => ({
       // A page component's headline is `title`; the PAGE's is `label`. Same
       // document one level apart with opposite spellings — the same trap
       // `dashboards.widgets` names, so it gets the same alias table.
-      aliases: { name: 'title', heading: 'title', text: 'label', caption: 'description', help: 'description', helpText: 'description', empty: 'emptyText', emptyState: 'emptyText', tabs: 'items' },
+      aliases: { name: 'title', heading: 'title', text: 'label', caption: 'description', help: 'description', helpText: 'description', empty: 'emptyText', emptyState: 'emptyText' },
       guidance: {
         submitLabel:
           '`submitLabel` was removed in @objectstack/spec 17 (ADR-0049) — its only '