fix(mp): 导航/请求健壮性 — reLaunch 去重 + 失败降级

- navigateToLogin 添加去重 + reLaunch 失败降级 redirectTo
- request.ts safeReLaunch 添加目标页检测 + 失败降级
- 退出登录 reLaunch 失败降级 redirectTo
- DoctorTabBar / 首页医生端跳转 reLaunch 失败降级
- 网络恢复时正确清理 toast 状态和定时器

apps/miniprogram/src/utils/navigate.ts

@@ -3,8 +3,26 @@ import Taro from '@tarojs/taro';
 const LOGIN_PAGE = '/pages/login/index';
 const MAX_PAGE_STACK = 9;
 
+// reLaunch 去重：避免 401 + 并发请求同时触发多个 reLaunch
+let reLaunchPromise: Promise<void> | null = null;
+
 export function navigateToLogin() {
-  Taro.reLaunch({ url: LOGIN_PAGE });
+  // 已在登录页，跳过
+  const pages = Taro.getCurrentPages();
+  const currentPath = pages[pages.length - 1]?.path || '';
+  if (currentPath.includes('pages/login')) return;
+
+  // 去重：上一个 reLaunch 还没完成就跳过
+  if (reLaunchPromise) return;
+  reLaunchPromise = Taro.reLaunch({ url: LOGIN_PAGE })
+    .catch((err) => {
+      console.warn('[navigate] reLaunch to login failed:', err);
+      // reLaunch 失败时降级为 redirectTo
+      Taro.redirectTo({ url: LOGIN_PAGE }).catch(() => {});
+    })
+    .then(() => {
+      setTimeout(() => { reLaunchPromise = null; }, 2000);
+    });
 }
 
 export function safeNavigateTo(url: string): void {