fix(mp): 患者端卡死深度审查修复 — CRITICAL 回归 + 并发保护 + 页栈溢出防护

CRITICAL:
- 咨询详情页 loadData 引用已删除的 pollingRef → 移除残余引用

HIGH:
- 401 重试递归改循环结构，避免并发限制器双 slot 占用
- 医生端 4 个列表页添加 loadingRef 防重入（consultation/alerts/dialysis/prescription）
- 新增 safeNavigateTo 页栈溢出保护（栈≥9 自动 redirectTo）

前期修复一并提交:
- 全局并发限制 MAX_CONCURRENT=8
- doRefresh 失败时完整清理 Storage + 重置缓存状态
- 401 跳转登录页修正
- 长轮询 generation counter 模式
- 首页/健康页 loadingRef + refreshToday 去重

apps/miniprogram/src/pages/health/index.tsx

@@ -1,4 +1,4 @@
-import { useState, useEffect } from 'react';
+import { useState, useEffect, useRef } from 'react';
 import { View, Text, Input } from '@tarojs/components';
 import Taro, { usePullDownRefresh } from '@tarojs/taro';
 import { useHealthStore } from '../../stores/health';
@@ -61,16 +61,18 @@ export default function Health() {
   const [trendLoading, setTrendLoading] = useState(false);
   const [aiSuggestions, setAiSuggestions] = useState<AiSuggestionItem[]>([]);
   const [thresholds, setThresholds] = useState<HealthThreshold[]>(DEFAULT_THRESHOLDS);
+  const loadingRef = useRef(false);
 
   useThrottledDidShow(() => {
-    if (!user) return;
+    if (!user || loadingRef.current) return;
     // 批量发起请求，避免串行 setState 级联重渲染
+    loadingRef.current = true;
     Promise.allSettled([
       refreshToday(),
       loadTrend(activeTab),
       loadAiSuggestions(),
       getHealthThresholds().then((t) => { if (t.length > 0) setThresholds(t); }),
-    ]);
+    ]).finally(() => { loadingRef.current = false; });
   }, 5000);
 
   usePullDownRefresh(() => {