feat(V39): 危急值管理增强 — 前端重构+DB修复+4/4 API通过

前端增强:
- CriticalValue pending页面: Tab切换(待确认/超时列表)
- 统计卡片: 待确认/已确认/已关闭/超时未确认
- 操作流程: 上报→确认接收→处理→关闭完整闭环
- API文件: 7个接口封装

数据库修复:
- critical_value: 添加delete_flag/create_by/update_by/update_time列
- 放宽encounter_id/lab_result_id/patient_id NOT NULL约束

后端修复:
- CriticalValue实体: 移除冗余delFlag，使用HisBaseEntity.deleteFlag
- CriticalValueAppServiceImpl: delFlag→deleteFlag迁移

测试: 4/4 API全部通过(上报/待确认列表/统计/超时列表)

healthlink-his-ui/src/views/criticalvalue/api.js

@@ -0,0 +1,9 @@
+import request from '@/utils/request'
+
+export function reportCriticalValue(data) { return request({ url: '/healthlink-his/api/v1/critical-value/report', method: 'post', data }) }
+export function confirmCriticalValue(id, params) { return request({ url: '/healthlink-his/api/v1/critical-value/confirm/' + id, method: 'put', params }) }
+export function processCriticalValue(id, params) { return request({ url: '/healthlink-his/api/v1/critical-value/process/' + id, method: 'put', params }) }
+export function closeCriticalValue(id) { return request({ url: '/healthlink-his/api/v1/critical-value/close/' + id, method: 'put' }) }
+export function getPendingList() { return request({ url: '/healthlink-his/api/v1/critical-value/pending', method: 'get' }) }
+export function getOverdueList() { return request({ url: '/healthlink-his/api/v1/critical-value/overdue', method: 'get' }) }
+export function getStatistics(params) { return request({ url: '/healthlink-his/api/v1/critical-value/statistics', method: 'get', params }) }