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/components/ui/DoctorTabBar/index.tsx

@@ -27,7 +27,9 @@ export default function DoctorTabBar({ active }: DoctorTabBarProps) {
 
   const handleTab = (tab: TabItem) => {
     if (tab.key === activeKey) return;
-    Taro.reLaunch({ url: tab.url });
+    Taro.reLaunch({ url: tab.url }).catch(() => {
+      Taro.redirectTo({ url: tab.url }).catch(() => {});
+    });
   };
 
   return (