The longest-task calculation spread every recorded task into Math.max, which
overflowed the call stack on traces carrying hundreds of thousands of tasks —
the same failure already fixed for collecting trace events.
A CPU sampling profile attributes native work to `(program)`, which during
streaming accounted for three quarters of all busy time and said nothing about
where it went. The timeline trace names that work, so the streaming report now
lists total and maximum time per trace event, skipping container events whose
duration already includes the work below them.
Adds `bun run profile:session`: creates a session, opens it in a real
browser, dispatches a prompt through the supported `openchamber session` CLI,
and records until the session reports itself idle. No input is synthesised, so
everything captured is the app reacting to its own event stream.
Streaming is judged by responsiveness rather than totals, so the report leads
with the long-task distribution, style recalculation and layout rates, frame
production, and the application's own stream counters.
Two failure modes are detected rather than reported as clean results. A session
belonging to a directory the browser is not viewing renders nothing and
produces a perfectly quiet profile, so the run verifies both new message
elements in the DOM and message-list render counters. And `RunTask` is only
emitted under the disabled-by-default timeline category, so a capture without
it reports zero long tasks; the missing-task case is now called out instead of
being shown as zero.
Metric helpers are shared with the idle profiler.
Bohdan Triapitsyn