fix(mp): 安全修复 + 健康Tab重构为总览

Phase 0 安全修复：
- 移除 secure-storage-aes.ts 硬编码 'hms-default-key' fallback
- production 模式空密钥时拒绝加解密（返回空/不加密）
- dev 模式保留明文兼容（warn 日志提醒）
- .env/.env.h5 注入随机加密密钥
- secureGet 明文 fallback 按环境分级处理
- 新增 8 个测试覆盖空密钥 dev/production 行为

Phase 1 健康Tab重构：
- health/index.tsx 从体征录入页改为健康总览Dashboard
- 新增今日体征摘要卡片（2x2 网格 + 状态标签）
- 新增快捷入口（录入体征/趋势/报告/用药）
- 新增告警提示卡片（待处理告警数量）
- 体征录入移至 pkg-health/input/index（已有页面）
- useHealthData → useHealthOverview（新增 alertCount）

首页增强：
- useHomeData 新增告警计数查询（listPatientAlerts）
- 首页新增告警提示卡片入口
- "记录体征"按钮改为跳转录入页而非健康Tab

apps/miniprogram/src/pages/index/useHomeData.ts

@@ -7,6 +7,7 @@ import * as appointmentApi from '@/services/appointment';
 import * as followupApi from '@/services/followup';
 import { listPendingSuggestions, type AiSuggestionItem } from '@/services/ai-analysis';
 import { notificationService } from '@/services/notification';
+import { listPatientAlerts } from '@/services/alert';
 
 export interface ReminderItem {
   id: string;
@@ -37,6 +38,7 @@ export function useHomeData() {
   const [reminders, setReminders] = useState<ReminderItem[]>([]);
   const [unreadCount, setUnreadCount] = useState(0);
   const [remindersLoading, setRemindersLoading] = useState(false);
+  const [alertCount, setAlertCount] = useState(0);
 
   const fetchData = async () => {
     const patientId = useAuthStore.getState().currentPatient?.id;
@@ -44,6 +46,7 @@ export function useHomeData() {
     refreshToday();
     loadReminders(patientId);
     loadUnread();
+    loadAlertCount(patientId);
     trackPageView('home');
   };
 
@@ -118,6 +121,15 @@ export function useHomeData() {
     }
   };
 
+  const loadAlertCount = async (patientId: string) => {
+    try {
+      const res = await listPatientAlerts(patientId, { status: 'pending', page: 1, page_size: 1 });
+      setAlertCount(res.total ?? 0);
+    } catch {
+      setAlertCount(0);
+    }
+  };
+
   const summary = todaySummary || {};
   const indicators = [!!summary.blood_pressure, !!summary.heart_rate, !!summary.blood_sugar, !!summary.weight];
   const completedCount = indicators.filter(Boolean).length;
@@ -149,6 +161,7 @@ export function useHomeData() {
     reminders,
     unreadCount,
     remindersLoading,
+    alertCount,
     indicatorCapsules,
     healthItems,
     completedCount,