## Summary
The run trace page loader serialized every span's raw OTel events (with
full properties) into the response, even though the tree UI only renders
the derived `timelineEvents` and the span detail panel refetches what it
needs. On event-heavy traces that inflated both the loader payload and
the server-side heap copies built per request. This PR keeps raw span
events server-side and pairs that with a few related trace-view
improvements:
- A new optional `TRACE_VIEW_EMERGENCY_SPAN_CAP` env var (unset by
default) clamps the trace summary and detailed trace summary span limits
on both event store paths, including the public run trace endpoint, so
operators can bound trace query sizes in one place without retuning the
per-store limits.
- The TreeView virtualizer resolved every rendered row with a linear
scan over the whole tree (and `getNodeProps` did the same via
`findIndex`); rows now resolve through memoized id lookup maps, which
matters once traces reach tens of thousands of spans.
- The run stream SSE lookup now applies the same organization membership
scoping as the rest of the run page presenters, for consistency.
Behavior is unchanged by default: the trace tree renders from the same
`timelineEvents` it always has, and the new cap only takes effect when
set.
Eric Allam
187c0476c3