如何在requestMeta当中设置 traceId， parentSpanId， spanId？

目前公司想用brpc， starlight做c++， java的通信， 需要接入第三方分布式链路追踪组件 目前选型是美团的cat 想请教下 starlight， brpc该如何优雅的设置这三个变量

ps：
求一个最新的群二维码 请教一些关于brpc starlight的问题

The issue identifies requestMeta and the brpc/Starlight communication path, but names no source file or test. Start by locating requestMeta handling and tracing-related entry points, then determine how the three IDs should be propagated across C++ and Java calls and what verification is needed.

Written by the indexing model from the issue text.