feat(desktop): add zh-CN localization support

ui/desktop/src/App.test.tsx

@@ -4,9 +4,12 @@
  * @vitest-environment jsdom
  */
 import React from 'react';
-import { screen, render, waitFor } from '@testing-library/react';
+import { screen, render as rtlRender, waitFor } from '@testing-library/react';
 import { vi, describe, it, expect, beforeEach, afterEach } from 'vitest';
 import { AppInner } from './App';
+import { LocalizationProvider } from './contexts/LocalizationContext';
+
+const render = (ui: React.ReactElement) => rtlRender(<LocalizationProvider>{ui}</LocalizationProvider>);
 
 // Set up globals for jsdom
 Object.defineProperty(window, 'location', {

ui/desktop/src/App.tsx

@@ -39,6 +39,7 @@ import 'react-toastify/dist/ReactToastify.css';
 import { useConfig } from './components/ConfigContext';
 import { ModelAndProviderProvider } from './components/ModelAndProviderContext';
 import { ThemeProvider } from './contexts/ThemeContext';
+import { LocalizationProvider } from './contexts/LocalizationContext';
 import PermissionSettingsView from './components/settings/permission/PermissionSetting';
 
 import ExtensionsView, { ExtensionsViewOptions } from './components/extensions/ExtensionsView';
@@ -702,13 +703,15 @@ export function AppInner() {
 export default function App() {
   return (
     <ThemeProvider>
-      <ModelAndProviderProvider>
-        <HashRouter>
-          <AppInner />
-        </HashRouter>
-        <AnnouncementModal />
-        <TelemetryOptOutModal controlled={false} />
-      </ModelAndProviderProvider>
+      <LocalizationProvider>
+        <ModelAndProviderProvider>
+          <HashRouter>
+            <AppInner />
+          </HashRouter>
+          <AnnouncementModal />
+          <TelemetryOptOutModal controlled={false} />
+        </ModelAndProviderProvider>
+      </LocalizationProvider>
     </ThemeProvider>
   );
 }

ui/desktop/src/components/ApiKeyTester.tsx

@@ -3,6 +3,7 @@ import { detectProvider } from '../api';
 import { Key } from './icons/Key';
 import { ArrowRight } from './icons/ArrowRight';
 import { Button } from './ui/button';
+import { useLocalization } from '../contexts/LocalizationContext';
 
 interface ApiKeyTesterProps {
   onSuccess: (provider: string, model: string, apiKey: string) => void;
@@ -16,6 +17,7 @@ interface DetectionResult {
 }
 
 export default function ApiKeyTester({ onSuccess, onStartTesting }: ApiKeyTesterProps) {
+  const { t } = useLocalization();
   const [apiKey, setApiKey] = useState('');
   const [isLoading, setIsLoading] = useState(false);
   const [result, setResult] = useState<DetectionResult | null>(null);
@@ -69,7 +71,7 @@ export default function ApiKeyTester({ onSuccess, onStartTesting }: ApiKeyTester
       {/* Recommended pill */}
       <div className="absolute -top-2 -right-2 sm:-top-3 sm:-right-3 z-20">
         <span className="inline-block px-2 py-1 text-xs font-medium bg-blue-600 text-white rounded-full">
-          Recommended if you have API access already
+          {t('apiKeyTester.recommended')}
         </span>
       </div>
 
@@ -78,10 +80,10 @@ export default function ApiKeyTester({ onSuccess, onStartTesting }: ApiKeyTester
           <Key className="w-4 h-4 text-text-primary flex-shrink-0" />
           <div className="flex flex-col sm:flex-row sm:items-center sm:gap-2">
             <h3 className="font-medium text-text-primary text-sm sm:text-base">
-              Quick Setup with API Key
+              {t('apiKeyTester.title')}
             </h3>
             <span className="text-text-secondary text-xs sm:text-sm">
-              Auto-detect your provider
+              {t('apiKeyTester.subtitle')}
             </span>
           </div>
         </div>
@@ -92,8 +94,8 @@ export default function ApiKeyTester({ onSuccess, onStartTesting }: ApiKeyTester
               ref={inputRef}
               type="password"
               value={apiKey}
-              onChange={(e) => setApiKey(e.target.value)}
-              placeholder="Enter your API key (OpenAI, Anthropic, Google, etc.)"
+                  onChange={(e) => setApiKey(e.target.value)}
+              placeholder={t('apiKeyTester.placeholder')}
               className="flex-1 px-3 py-2 border rounded-lg bg-background-primary text-text-primary placeholder:text-text-secondary focus:outline-none focus:ring-2 focus:ring-blue-500 focus:border-transparent"
               disabled={isLoading}
               onKeyDown={(e) => {
@@ -120,7 +122,7 @@ export default function ApiKeyTester({ onSuccess, onStartTesting }: ApiKeyTester
           {isLoading && (
             <div className="flex items-center gap-2 px-3 py-2 bg-background-secondary rounded text-sm text-text-secondary">
               <div className="w-3 h-3 border-2 border-current border-t-transparent rounded-full animate-spin"></div>
-              <span>Detecting provider and validating key...</span>
+              <span>{t('apiKeyTester.detecting')}</span>
             </div>
           )}
 
@@ -129,9 +131,14 @@ export default function ApiKeyTester({ onSuccess, onStartTesting }: ApiKeyTester
             <div className="flex items-center gap-2 text-sm p-3 rounded-lg bg-green-50 text-green-800 border border-green-200 dark:bg-green-900/20 dark:text-green-200 dark:border-green-800">
               <span>✅</span>
               <div className="flex-1">
-                <div className="font-medium">Detected {result.provider}</div>
+                <div className="font-medium">
+                  {t('apiKeyTester.detectedProvider', { provider: result.provider })}
+                </div>
                 <div className="text-green-600 dark:text-green-400 text-xs mt-1">
-                  Model: {result.model} ({result.totalModels} models available)
+                  {t('apiKeyTester.modelSummary', {
+                    model: result.model,
+                    count: result.totalModels,
+                  })}
                 </div>
               </div>
             </div>
@@ -143,33 +150,36 @@ export default function ApiKeyTester({ onSuccess, onStartTesting }: ApiKeyTester
               <div className="flex items-center gap-2 text-sm p-3 rounded-lg bg-red-50 text-red-800 border border-red-200 dark:bg-red-900/20 dark:text-red-200 dark:border-red-800">
                 <span>❌</span>
                 <div className="flex-1">
-                  <div className="font-medium">Provider Detection Failed</div>
+                  <div className="font-medium">{t('apiKeyTester.detectionFailedTitle')}</div>
                   <div className="text-red-600 dark:text-red-400 text-xs mt-1">
-                    Could not detect provider from API key
+                    {t('apiKeyTester.detectionFailedDescription')}
                   </div>
                 </div>
               </div>
               <div className="ml-6 space-y-1">
-                <p className="text-xs font-medium text-text-secondary">Suggestions:</p>
+                <p className="text-xs font-medium text-text-secondary">
+                  {t('apiKeyTester.suggestions')}
+                </p>
                 <ul className="text-xs text-text-secondary space-y-1">
                   <li className="flex items-start gap-1">
                     <span className="text-blue-500 mt-0.5">•</span>
-                    <span>
-                      Make sure you are using a valid API key from OpenAI, Anthropic, Google, Groq,
-                      or xAI
-                    </span>
+                    <span>{t('apiKeyTester.suggestionValidKey')}</span>
                   </li>
                   <li className="flex items-start gap-1">
                     <span className="text-blue-500 mt-0.5">•</span>
-                    <span>Check that the key is complete and not truncated</span>
+                    <span>{t('apiKeyTester.suggestionCompleteKey')}</span>
                   </li>
                   <li className="flex items-start gap-1">
                     <span className="text-blue-500 mt-0.5">•</span>
-                    <span>Verify your API key is active and has sufficient credits</span>
+                    <span>{t('apiKeyTester.suggestionCredits')}</span>
                   </li>
                   <li className="flex items-start gap-1">
                     <span className="text-blue-500 mt-0.5">•</span>
-                    <span>For local Ollama setup, use the "Other Providers" section below</span>
+                    <span>
+                      {t('apiKeyTester.suggestionLocalOllama', {
+                        section: t('providers.onboardingTitle'),
+                      })}
+                    </span>
                   </li>
                 </ul>
               </div>