feat: Apply localization to Login, Dashboard, and Navigation (Phase 9 - Batch 1)

**Pages Localized:**
- Login page: All UI strings (titles, labels, buttons, links)
- Dashboard page: Welcome message, quick actions, daily summary, predictions
- AppShell: Connection status and presence indicators
- MobileNav: Menu items and app branding
- TabBar: Bottom navigation labels

**Translation Files:**
- Created dashboard.json for all 5 languages (en, es, fr, pt, zh)
- Enhanced common.json with navigation and connection strings
- Updated i18n config to include dashboard namespace

**Languages Supported:**
- English, Spanish, French, Portuguese, Chinese (Simplified)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

maternal-web/components/layouts/TabBar/TabBar.tsx

@@ -9,17 +9,19 @@ import {
   Insights,
   Settings,
 } from '@mui/icons-material';
+import { useTranslation } from '@/hooks/useTranslation';
 
 export const TabBar = () => {
+  const { t } = useTranslation('common');
   const router = useRouter();
   const pathname = usePathname();
 
   const tabs = [
-    { label: 'Home', icon: <Home />, value: '/' },
-    { label: 'Track', icon: <Timeline />, value: '/track' },
-    { label: 'AI Chat', icon: <Chat />, value: '/ai-assistant' },
-    { label: 'Insights', icon: <Insights />, value: '/insights' },
-    { label: 'Settings', icon: <Settings />, value: '/settings' },
+    { label: t('navigation.home'), icon: <Home />, value: '/' },
+    { label: t('navigation.track'), icon: <Timeline />, value: '/track' },
+    { label: t('navigation.aiChat'), icon: <Chat />, value: '/ai-assistant' },
+    { label: t('navigation.insights'), icon: <Insights />, value: '/insights' },
+    { label: t('navigation.settings'), icon: <Settings />, value: '/settings' },
   ];
 
   return (