{
  "schema_version": 1,
  "kind": "timeline",
  "data_kind": "synthetic-demo",
  "source": "组件演示，不代表真实日程；等距里程碑",
  "items": [
    {"date": "第一周", "label": "需求确认"},
    {"date": "第二周", "label": "原型验证"},
    {"date": "第四周", "label": "联合测试"},
    {"date": "第五周", "label": "交付审阅"}
  ]
}