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/locales/zh/dashboard.json

@@ -0,0 +1,30 @@
+{
+  "welcomeBack": "欢迎回来",
+  "welcomeBackWithName": "欢迎回来，{{name}}！",
+  "subtitle": "追踪您孩子的活动并获得AI驱动的见解",
+  "quickActions": {
+    "title": "快速操作",
+    "feeding": "喂养",
+    "sleep": "睡眠",
+    "diaper": "尿布",
+    "medicine": "药物",
+    "activities": "活动",
+    "aiAssistant": "AI助手",
+    "navigateTo": "导航到{{action}}"
+  },
+  "summary": {
+    "title": "今日总结",
+    "titleWithChild": "今日总结 - {{childName}}",
+    "feedings": "喂养次数",
+    "sleep": "睡眠",
+    "diapers": "尿布",
+    "medications": "药物",
+    "noChild": "添加孩子以开始追踪",
+    "noActivities": "今天没有追踪任何活动"
+  },
+  "predictions": {
+    "title": "下一个预测活动",
+    "napTime": "{{minutes}}分钟后小睡时间",
+    "basedOnPatterns": "基于您孩子的睡眠模式"
+  }
+}