Out of order log lines

A log collector merges lines from many app instances, and clock skew sometimes makes timestamps go backwards. Each line starts with a sortable timestamp string like "2026-07-01T10:00:05" followed by a space and the rest of the entry. Comparing these timestamps as plain strings gives chronological order. Return how many lines arrive strictly earlier than the line directly before them — that is, count positions i > 0 where timestamp[i] < timestamp[i-1]. Equal neighboring timestamps are fine and count as in order.