fix(i18n): return flat translations dict from kernel service + regression tests

The createKernel i18n service's getTranslations returned
{ locale, translations } instead of the flat Record<string, any>
expected by the spec II18nService interface. The HttpDispatcher
wraps the return in { data: { locale, translations } }, so the
extra layer caused /api/v1/i18n/translations/:lang to return
empty or double-nested translations.

Now returns resolveI18nTranslations() directly. Added 6 regression
tests covering: kernel service, HttpDispatcher, and MSW handler.

Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>
Agent-Logs-Url: https://github.com/objectstack-ai/objectui/sessions/9e014d2c-cb4d-4779-8774-216d48126f73

Author: Copilot

apps/console/src/__tests__/i18n-translations.test.ts

@@ -0,0 +1,114 @@
+/**
+ * i18n Translations Pipeline Tests
+ *
+ * Validates that the i18n translation pipeline delivers CRM translations
+ * correctly through all code paths:
+ *  - Kernel service: getTranslations returns flat dict (not wrapped)
+ *  - HttpDispatcher: wraps into standard spec envelope
+ *  - MSW handler: returns correct { data: { locale, translations } }
+ *
+ * Regression test for empty translations:{} response.
+ */
+import { describe, it, expect, beforeAll, afterAll } from 'vitest';
+import { setupServer } from 'msw/node';
+import { createKernel, type KernelResult } from '../mocks/createKernel';
+import { createAuthHandlers } from '../mocks/authHandlers';
+import appConfig from '../../objectstack.shared';
+import { crmLocales } from '@object-ui/example-crm';
+
+// Expected values from the CRM i18n bundles — avoid hard-coding in assertions
+const EXPECTED_ZH_ACCOUNT_LABEL = crmLocales.zh.objects.account.label;
+const EXPECTED_EN_ACCOUNT_LABEL = crmLocales.en.objects.account.label;
+
+describe('i18n translations pipeline', () => {
+  let result: KernelResult;
+  let server: ReturnType<typeof setupServer>;
+
+  beforeAll(async () => {
+    result = await createKernel({
+      appConfig,
+      persistence: false,
+      mswOptions: {
+        enableBrowser: false,
+        baseUrl: '/api/v1',
+        logRequests: false,
+        customHandlers: [
+          ...createAuthHandlers('/api/v1/auth'),
+        ],
+      },
+    });
+
+    const handlers = result.mswPlugin?.getHandlers() ?? [];
+    server = setupServer(...handlers);
+    server.listen({ onUnhandledRequest: 'bypass' });
+  });
+
+  afterAll(() => {
+    server?.close();
+  });
+
+  // ── Kernel service layer ───────────────────────────────────────────
+
+  it('kernel i18n service returns flat translations dict (not wrapped)', () => {
+    const i18nService = result.kernel.getService('i18n');
+    const translations = i18nService.getTranslations('zh');
+
+    // Must NOT have the { locale, translations } wrapper
+    expect(translations).not.toHaveProperty('locale');
+    expect(translations).toHaveProperty('crm');
+    expect(translations.crm.objects.account.label).toBe(EXPECTED_ZH_ACCOUNT_LABEL);
+  });
+
+  it('kernel i18n service returns English translations', () => {
+    const i18nService = result.kernel.getService('i18n');
+    const translations = i18nService.getTranslations('en');
+
+    expect(translations.crm.objects.account.label).toBe(EXPECTED_EN_ACCOUNT_LABEL);
+  });
+
+  it('kernel i18n service returns empty for unknown locale', () => {
+    const i18nService = result.kernel.getService('i18n');
+    const translations = i18nService.getTranslations('xx');
+
+    expect(Object.keys(translations)).toHaveLength(0);
+  });
+
+  // ── HttpDispatcher layer ───────────────────────────────────────────
+
+  it('HttpDispatcher returns populated translations in spec envelope', async () => {
+    const { HttpDispatcher } = await import('@objectstack/runtime');
+    const dispatcher = new HttpDispatcher(result.kernel);
+
+    const dispatchResult = await dispatcher.handleI18n('/translations/zh', 'GET', {}, {});
+
+    expect(dispatchResult.handled).toBe(true);
+    expect(dispatchResult.response?.status).toBe(200);
+    const body = dispatchResult.response?.body;
+    expect(body?.success).toBe(true);
+    expect(body?.data?.locale).toBe('zh');
+    expect(Object.keys(body?.data?.translations ?? {}).length).toBeGreaterThan(0);
+    expect(body?.data?.translations?.crm?.objects?.account?.label).toBe(EXPECTED_ZH_ACCOUNT_LABEL);
+  });
+
+  // ── MSW handler layer (fetch) ──────────────────────────────────────
+
+  it('GET /api/v1/i18n/translations/zh returns CRM zh translations', async () => {
+    const res = await fetch('http://localhost/api/v1/i18n/translations/zh');
+    expect(res.ok).toBe(true);
+
+    const json = await res.json();
+    const translations = json?.data?.translations;
+
+    expect(translations).toBeDefined();
+    expect(Object.keys(translations).length).toBeGreaterThan(0);
+    expect(translations.crm).toBeDefined();
+    expect(translations.crm.objects.account.label).toBe(EXPECTED_ZH_ACCOUNT_LABEL);
+  });
+
+  it('GET /api/v1/i18n/translations/en returns CRM en translations', async () => {
+    const res = await fetch('http://localhost/api/v1/i18n/translations/en');
+    const json = await res.json();
+
+    expect(json?.data?.translations?.crm?.objects?.account?.label).toBe(EXPECTED_EN_ACCOUNT_LABEL);
+  });
+});