收紧后端 TypeScript：统一 Json 类型与 TaskContext 契约

关闭 allowJs；集中 JsonObject 定义并替换分散 any 别名；parseTaskContext 返回 TaskContext；任务详情 API 标注 AdminTaskDetailView；测试减少 as any。

apps/backend/src/services/bootstrap/fulfillment-bootstrap-service.ts

@@ -1,3 +1,4 @@
+import type { JsonObject } from '../../types/json.js'
 import {
   listFulfillmentProfileRequirements,
   replaceFulfillmentProfileRequirements,
@@ -6,7 +7,6 @@ import {
 } from '../../repositories/fulfillment-profile-repo.js'
 import { nowIso } from '../../utils/time.js'
 
-type JsonObject = Record<string, any>
 type CoreProfile = {
   profileKey: string
   name: string