fix(cli): isolate server request traces

[StarpTech]

Summary

• stop long-lived server lifecycle spans from parenting every HTTP request
• remove the ambient Tracer.ParentSpan when installing the request handler
• preserve inbound traceparent continuation and downstream propagation

Problem

Effect's Node HTTP server captures the current context when installing its handler. Previously that context contained the server lifecycle parent:

server lifecycle trace
├─ request A
├─ request B
└─ request C

Unrelated requests therefore shared one trace ID.

Fix

Process-lifetime boundaries are untraced, and handler installation explicitly omits Tracer.ParentSpan:

client traceparent (when supplied)
└─ request A
request B root (without client context)

Request tracing remains enabled. Headerless requests receive independent roots, while requests with traceparent continue the client trace.

Testing

• in-process regression covering two independent roots and inbound context continuation
• CLI tests: 32 passed
• server tests: 10 passed
• CLI, server, and workspace typechecks passed