feat(mp): 医护端告警列表/详情页 + DoctorHome 告警 banner 增强

- 新增告警列表页：按状态筛选、分页、严重程度/状态标签
- 新增告警详情页：完整信息展示 + 确认/忽略/恢复操作
- doctor.ts 新增 listAlerts/acknowledgeAlert/dismissAlert/resolveAlert API
- DoctorHome 告警 banner 跳转目标改为告警列表页
- 注册 alerts/index + alerts/detail/index 到 doctor subPackage

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

@@ -88,7 +88,7 @@ export default function DoctorHome() {
         <View className='doctor-home__alert'>
           <Text className='doctor-home__alert-icon'>!</Text>
           <Text className='doctor-home__alert-text'>{alertCount} 位患者体征异常</Text>
-          <Text className='doctor-home__alert-link' onClick={() => Taro.navigateTo({ url: '/pages/doctor/patients/index' })}>查看 →</Text>
+          <Text className='doctor-home__alert-link' onClick={() => Taro.navigateTo({ url: '/pages/doctor/alerts/index' })}>查看 →</Text>
         </View>
       )}