@@ -0,0 +1,24 @@
+---
+"@objectstack/cli": patch
+---
+
+fix(cli): `os lint` and `os i18n check` ask for the label of a navigation item another package contributes into an app (#24993)
+
+Clause-②: no
+Metadata-protocol: none
+
+A package can add items to an app it does not own through `manifest.navigationContributions`. The runtime merges those items into the app's navigation and shows each one's label from `apps.APP.navigation.ID.label`, where `APP` is the app the item is contributed to. `os validate` already accepted that key. But the i18n extractor only read each app's own `navigation`, so a contributed item's key was never expected: deleting its translation left `os lint --strict` and `os i18n check` green. The same deletion on an item the app declares itself was reported.
+
+Now a contributed item is expected under its target app, from either place a contribution is declared: the stack's own `manifest`, or a package's manifest inside a `composeStacks(…, { manifest: 'preserve' })` artifact. Its source text is its own `label`. A contributed group's children are expected as an app's own group children are. An item the app also declares keeps the app's entry, and a contribution read from two places is expected once.
+
+**What you may see.** A project that contributes navigation and declares a locale beyond its default now gets an `i18n/missing-navigation` finding for each contributed item that locale's pack does not translate. It is a warning by default, which `os lint --strict` fails on. Under `os lint --i18n-strict` or `os i18n check --strict` it is an error, like every other missing translation. To clear them, translate the key under the target app in that locale's pack, for example:
+
+```ts
+apps: {
+  crm_enterprise: {
+    navigation: { nav_case: { label: '工单' } },
+  },
+},
+```
+
+`os i18n extract` now writes these slots too, and keeps the strings a pack already translates. No key, schema or export changes: the key was already part of the translation contract.
@@ -93,6 +93,9 @@
  *   globalActions.<action>.params.<param>.* / .resultDialog.* (same shape as object actions)
  *   apps.<app>.label / .description
  *   apps.<app>.navigation.<id>.label
+ *     ^ an item another package CONTRIBUTES into the app through
+ *       `manifest.navigationContributions` too, keyed under the TARGET app
+ *       (#24993; see `navigationContributionsOf`)
  *   dashboards.<dash>.label / .description
  *   dashboards.<dash>.widgets.<w>.title / .description
  *   datasets.<dataset>.label / .description
@@ -1451,6 +1454,22 @@ export function collectExpectedEntries(
     walkNavigation(nav, appName, out);
   }
 
+  // ── Contributed navigation (ADR-0029 D7, #24993) ─────────────────
+  // An item a package injects into another package's app never enters that
+  // app's authored `navigation`: the runtime folds it in on every read
+  // (`SchemaRegistry.applyNavContributions`) and `translateApp` then resolves
+  // its label from `apps.<target>.navigation.<id>.label` — the key
+  // `translation-target-unknown` already accepts for a contributed item
+  // (#18203). Walked AFTER the apps' own trees and by the same
+  // `walkNavigation`, so a contributed group's children follow the rule an own
+  // group's do, and an id an app also declares keeps its own entry
+  // (`dedupeByPath`, first emission wins).
+  for (const contribution of navigationContributionsOf(config)) {
+    const targetApp = contribution?.app;
+    if (typeof targetApp !== 'string' || targetApp.length === 0) continue;
+    if (Array.isArray(contribution.items)) walkNavigation(contribution.items, targetApp, out);
+  }
+
   // ── Dashboards + widgets ─────────────────────────────────────────
   const dashboards: any[] = Array.isArray(config?.dashboards) ? config.dashboards : [];
   for (const dash of dashboards) {
@@ -2146,6 +2165,45 @@ function walkNavigation(nav: any[], appName: string, out: ExpectedEntry[]): void
   }
 }
 
+/**
+ * Every `navigationContributions[]` entry the stack carries, from the two
+ * carriers `translation-target-unknown` reads (`contributedNavItemsByApp` in
+ * `@objectstack/lint`'s `validate-translation-references.ts`), so the keys
+ * coverage expects are the keys that rule accepts:
+ *
+ *   1. `manifest.navigationContributions` — where a single-`defineStack`
+ *      project's contributions live;
+ *   2. `packages[].manifest.navigationContributions` — the ADR-0130 D4 artifact
+ *      entry, whose `manifest` is the assembled package body. On a
+ *      `composeStacks(…, { manifest: 'preserve' })` stack this is the only
+ *      place a module's contributions sit: the singular top-level `manifest`
+ *      is one package's copy (the `'last'` pick), usually the app's.
+ *
+ * Both are read unconditionally, as the rule reads them. Where the top-level
+ * manifest IS a copy of a contributing package's, the two carriers yield the
+ * same items and `dedupeByPath` keeps one entry per key.
+ *
+ * ⛔ The rule's reader is not imported: it is module-private to
+ * `@objectstack/lint`. This copy is held to it by
+ * `test/i18n-contributed-nav-coverage.test.ts`, which runs the rule over a
+ * bundle carrying every contributed key this walk expects.
+ *
+ * Not seen, here as there: a contribution registered imperatively from a
+ * plugin's `init` (`engine.registerAppNavContribution`) is not metadata;
+ * `packages/cli/scripts/check-app-nav-i18n.mjs` boots a composition to judge
+ * that population.
+ */
+function navigationContributionsOf(config: any): any[] {
+  const out: any[] = [];
+  const add = (list: unknown): void => {
+    if (Array.isArray(list)) out.push(...list);
+  };
+  add(config?.manifest?.navigationContributions);
+  const packages: unknown[] = Array.isArray(config?.packages) ? config.packages : [];
+  for (const entry of packages) add((entry as any)?.manifest?.navigationContributions);
+  return out;
+}
+
 // ─── Filter + bundle assembly ──────────────────────────────────────────
 
 function passesFilter(entry: ExpectedEntry, filter?: RegExp): boolean {
 
@@ -0,0 +1,242 @@
+// Copyright (c) 2026 ObjectStack contributors. Apache-2.0 license.
+//
+// objectstack#24993 — a navigation item a package CONTRIBUTES into another
+// package's app (`manifest.navigationContributions`, ADR-0029 D7) owes its
+// translation under the TARGET app, like an item the app declares itself.
+//
+// The runtime folds a contributed item into the target app's navigation and
+// `translateApp` resolves its label from `apps.<target>.navigation.<id>.label`;
+// `translation-target-unknown` accepts that key (#18203). The walker read
+// `apps[].navigation` only, so the key was never expected: deleting a
+// contributed item's zh-CN label left `os lint --strict` and `os i18n check`
+// green, measured on HotCRM's `nav_case`, while the same deletion on one of
+// the app's own items reported `i18n/missing-navigation`.
+//
+// The fixture is the card's shape: a service module contributing into the
+// app's group and adding a group of its own, composed module-first with
+// `manifest: 'preserve'`, so the contributions live only in the module's
+// `packages[]` body. Both doors hand `computeI18nCoverage` the
+// `authoringRuleUnionStack` of that composition, which is what these pins do.
+
+import { describe, it, expect } from 'vitest';
+import { composeStacks, defineStack } from '@objectstack/spec';
+import { TRANSLATION_TARGET_UNKNOWN, validateTranslationReferences } from '@objectstack/lint';
+
+import { collectExpectedEntries } from '../src/utils/i18n-extract.js';
+import { computeI18nCoverage } from '../src/utils/i18n-coverage.js';
+import { authoringRuleUnionStack } from '../src/utils/stack-collections.js';
+
+const I18N = { defaultLocale: 'en', supportedLocales: ['en', 'zh-CN'], fallbackLocale: 'en' };
+const engines = { protocol: '^18' };
+
+const appManifest = {
+  id: 'com.example.cnav.app', name: 'Contributed Nav App', namespace: 'cnv', version: '1.0.0', type: 'app', engines,
+};
+
+/** Into the app's own group, and a group of the module's own with a child. */
+const CONTRIBUTIONS = [
+  {
+    app: 'cnv_desk',
+    group: 'grp_service',
+    items: [{ id: 'nav_case', type: 'object', objectName: 'cnv_case', label: 'Cases' }],
+  },
+  {
+    app: 'cnv_desk',
+    items: [{
+      id: 'grp_knowledge',
+      type: 'group',
+      label: 'Knowledge',
+      children: [{ id: 'nav_article', type: 'object', objectName: 'cnv_article', label: 'Articles' }],
+    }],
+  },
+];
+
+const svcManifest = {
+  id: 'com.example.cnav.svc', name: 'Contributed Nav Service', namespace: 'cnv', version: '1.0.0', type: 'module', engines,
+  navigationContributions: CONTRIBUTIONS,
+};
+
+const object = (name: string, label: string) => ({
+  name, label, pluralLabel: label, sharingModel: 'private',
+  fields: { name: { name: 'name', type: 'text', label: 'Name', required: true } },
+});
+
+const app = {
+  name: 'cnv_desk',
+  label: 'Desk',
+  navigation: [{
+    id: 'grp_service',
+    type: 'group',
+    label: 'Service',
+    children: [{ id: 'nav_accounts', type: 'object', objectName: 'cnv_account', label: 'Accounts' }],
+  }],
+};
+
+/** The zh-CN navigation labels, every one present; a case deletes one. */
+const OWN_NAV_ZH = { grp_service: { label: '服务' }, nav_accounts: { label: '客户' } };
+const CONTRIBUTED_NAV_ZH = { nav_case: { label: '工单' }, grp_knowledge: { label: '知识' }, nav_article: { label: '文章' } };
+
+const without = (labels: Record<string, unknown>, id?: string) =>
+  Object.fromEntries(Object.entries(labels).filter(([key]) => key !== id));
+
+/**
+ * The app package's pack carries every navigation label, the contributed ones
+ * included — the layout HotCRM's packs were measured in (#18203). A pack's
+ * `apps.APP` entry requires the app's own `label`, so a module could ship the
+ * contributed labels itself only by restating it.
+ */
+function stacks(drop?: string) {
+  const appStack = defineStack({
+    manifest: appManifest,
+    objects: [object('cnv_account', 'Account')],
+    apps: [app],
+    i18n: I18N,
+    translations: [{
+      'zh-CN': { apps: { cnv_desk: { label: '服务台', navigation: without({ ...OWN_NAV_ZH, ...CONTRIBUTED_NAV_ZH }, drop) } } },
+    }],
+  } as any);
+  const svcStack = defineStack({
+    manifest: svcManifest,
+    objects: [object('cnv_case', 'Case'), object('cnv_article', 'Article')],
+    i18n: I18N,
+  } as any);
+  return { appStack, svcStack };
+}
+
+/** Module first, as HotCRM composes it: the top-level manifest is the app's. */
+function composed(drop?: string): Record<string, unknown> {
+  const { appStack, svcStack } = stacks(drop);
+  return authoringRuleUnionStack(composeStacks([svcStack, appStack], { manifest: 'preserve' }) as any);
+}
+
+const navEntries = (config: any) =>
+  collectExpectedEntries(config).filter((e) => e.path[0] === 'apps' && e.path[2] === 'navigation');
+
+const zhNavIssueKeys = (config: any) =>
+  computeI18nCoverage(config, { strict: true }).issues
+    .filter((i) => i.locale === 'zh-CN' && i.source === 'navigation')
+    .map((i) => i.key);
+
+describe('what the walker expects from a contributed navigation item (#24993)', () => {
+  it('reads the contributions from the module\'s package body alone — the fixture is the card\'s shape', () => {
+    const stack = composed() as any;
+    expect(stack.manifest.navigationContributions).toBeUndefined();
+    expect(stack.packages.map((p: any) => p.manifest.navigationContributions?.length ?? 0)).toEqual([2, 0]);
+  });
+
+  it('expects each contributed item under the TARGET app, seeded with its own label, after the app\'s own items', () => {
+    const entries = navEntries(composed());
+    expect(entries.map((e) => e.path.join('.'))).toEqual([
+      'apps.cnv_desk.navigation.grp_service.label',
+      'apps.cnv_desk.navigation.nav_accounts.label',
+      'apps.cnv_desk.navigation.nav_case.label',
+      'apps.cnv_desk.navigation.grp_knowledge.label',
+      'apps.cnv_desk.navigation.nav_article.label',
+    ]);
+    expect(entries[2]).toMatchObject({ sourceValue: 'Cases', inline: 'Cases', source: 'navigation', appName: 'cnv_desk' });
+    expect(entries[4]).toMatchObject({ sourceValue: 'Articles', inline: 'Articles', source: 'navigation', appName: 'cnv_desk' });
+  });
+
+  it('reads a single stack\'s own manifest too, keyed under an app the stack only contributes into', () => {
+    const single = defineStack({
+      manifest: { ...svcManifest, navigationContributions: [{ app: 'crm_enterprise', items: CONTRIBUTIONS[0].items }] },
+      objects: [object('cnv_case', 'Case')],
+    } as any);
+    expect(navEntries(single).map((e) => e.path.join('.'))).toEqual(['apps.crm_enterprise.navigation.nav_case.label']);
+  });
+
+  it('expects each key once when the top-level manifest is the contributor\'s copy', () => {
+    const { appStack, svcStack } = stacks();
+    const appLast = authoringRuleUnionStack(composeStacks([appStack, svcStack], { manifest: 'preserve' }) as any) as any;
+    // Both carriers hold the module's contributions here.
+    expect(appLast.manifest.navigationContributions).toHaveLength(2);
+    expect(navEntries(appLast).map((e) => e.path.join('.'))).toEqual([
+      'apps.cnv_desk.navigation.grp_service.label',
+      'apps.cnv_desk.navigation.nav_accounts.label',
+      'apps.cnv_desk.navigation.nav_case.label',
+      'apps.cnv_desk.navigation.grp_knowledge.label',
+      'apps.cnv_desk.navigation.nav_article.label',
+    ]);
+  });
+
+  it('keeps the app\'s own entry when a contribution reuses one of its ids', () => {
+    const config = {
+      apps: [app],
+      manifest: { navigationContributions: [{ app: 'cnv_desk', items: [{ id: 'nav_accounts', type: 'url', url: '/x', label: 'Elsewhere' }] }] },
+    };
+    const entries = navEntries(config);
+    expect(entries.map((e) => e.path.join('.'))).toEqual([
+      'apps.cnv_desk.navigation.grp_service.label',
+      'apps.cnv_desk.navigation.nav_accounts.label',
+    ]);
+    expect(entries[1].sourceValue).toBe('Accounts');
+  });
+});
+
+describe('the coverage gate reports a missing contributed item as it reports an own one (#24993)', () => {
+  it('reports no navigation gap while every label is translated', () => {
+    expect(zhNavIssueKeys(composed())).toEqual([]);
+  });
+
+  it('reports a deleted contributed item', () => {
+    expect(zhNavIssueKeys(composed('nav_case'))).toEqual(['apps.cnv_desk.navigation.nav_case.label']);
+  });
+
+  it('reports a deleted child of a contributed group', () => {
+    expect(zhNavIssueKeys(composed('nav_article'))).toEqual(['apps.cnv_desk.navigation.nav_article.label']);
+  });
+
+  it('control: reports a deleted item the app declares itself, as before', () => {
+    expect(zhNavIssueKeys(composed('nav_accounts'))).toEqual(['apps.cnv_desk.navigation.nav_accounts.label']);
+  });
+
+  it('reports the deleted key once when both carriers hold the contribution', () => {
+    const { appStack, svcStack } = stacks('nav_case');
+    const appLast = authoringRuleUnionStack(composeStacks([appStack, svcStack], { manifest: 'preserve' }) as any);
+    expect(zhNavIssueKeys(appLast)).toEqual(['apps.cnv_desk.navigation.nav_case.label']);
+  });
+});
+
+describe('every contributed key the walker expects is one translation-target-unknown accepts (#24993)', () => {
+  /** A zh-CN bundle carrying exactly the navigation keys the walker expects. */
+  const bundleOf = (config: any) => {
+    const navigation: Record<string, { label: string }> = {};
+    const apps: Record<string, { navigation: typeof navigation }> = {};
+    for (const entry of navEntries(config)) {
+      const [, appName, , id] = entry.path;
+      apps[appName] ??= { navigation: {} };
+      apps[appName].navigation[id] = { label: 'x' };
+    }
+    return { 'zh-CN': { apps } };
+  };
+  const unknownTargets = (stack: any, bundle: unknown) =>
+    validateTranslationReferences({ ...stack, translations: [bundle] })
+      .filter((f) => f.rule === TRANSLATION_TARGET_UNKNOWN)
+      .map((f) => f.path);
+
+  it('accepts every expected key on the composed stack', () => {
+    const stack = composed();
+    const bundle = bundleOf(stack);
+    // Not vacuous: the bundle carries the contributed ids, not only the app's own.
+    expect(Object.keys(bundle['zh-CN'].apps.cnv_desk.navigation)).toEqual([
+      'grp_service', 'nav_accounts', 'nav_case', 'grp_knowledge', 'nav_article',
+    ]);
+    expect(unknownTargets(stack, bundle)).toEqual([]);
+  });
+
+  it('accepts the expected key under an app the stack only contributes into', () => {
+    const single = defineStack({
+      manifest: { ...svcManifest, navigationContributions: [{ app: 'crm_enterprise', items: CONTRIBUTIONS[0].items }] },
+      objects: [object('cnv_case', 'Case')],
+    } as any) as any;
+    const bundle = bundleOf(single);
+    expect(Object.keys(bundle['zh-CN'].apps)).toEqual(['crm_enterprise']);
+    expect(unknownTargets(single, bundle)).toEqual([]);
+  });
+
+  it('control: still refuses a navigation id nothing declares or contributes', () => {
+    const stack = composed();
+    const bundle = { 'zh-CN': { apps: { cnv_desk: { navigation: { nav_ghost: { label: 'x' } } } } } };
+    expect(unknownTargets(stack, bundle)).toEqual(['translations[0]["zh-CN"].apps.cnv_desk.navigation.nav_ghost']);
+  });
+});