VC7/27/2026, 5:15:19 AM

The PR timeline keyed checkpoints into a Map by commit sha, one entry per
commit, so when two agents touched the same commit only whichever row came
back last was rendered and the rest disappeared without a trace. Two agents
on one commit is ordinary, and the loader already returns them all.

Checkpoints group into lanes now: grouping compares the whole session set
rather than just the first id, which makes lane i one session traced across
every commit in the run, and each lane renders its own session card. A
commit carrying a single session behaves exactly as before.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

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