feat(stats): hand transactions to the tracker over a channel, not a lock - #80

Bugbot Analysis Progress (5m 52s elapsed)

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✅ Completed bug detection (5m 41s)
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Final Result: Bugbot completed review - no new issues found! ✅

Request ID: serverGenReqId_00cec04c-a33b-4b33-8347-28de5feb3755