Two durations were being conflated. How long the thread has not moved is the defect; how long the
span it is inside has been open is only where it is stuck, and for an enclosing span that is the
whole session — which is why the live log said "has been running 360380 ms" and then "was in there
at least 360406 ms" about a 150 ms hiccup.
So both, labelled, and the thread's name beside them: the span it is stuck in may be unnamed, since
an enclosing `info_span!` carries no `name` field for `on_new_span` to record, and then the thread
is the only thing the report can name. Before this, such a stall printed `span #2473901162497` and
nothing else.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SgstFWtn1RxEJ5kVrpgYwn
gromandClaude Opus 5
4393bde4ec