The repair retires a dropped row onto the survivor before it. With nothing kept
before it (a stray tool result or an unanswered tool call as the first active row)
the row stayed unnamed, and an in-place compaction cloned it behind the compacted
set. The first dict the pass keeps now stands for the rows dropped ahead of it, by
row id or by count.
The leading-drop case comes from #129162.
Co-authored-by: JerryLiu369 <953639086@qq.com>
(cherry picked from commit 2facd175120acfd99b3e566bd1647e0f4b7767fb)
(cherry picked from commit 90faa5025ba4fd88a8cce967856c592f23776f27)
6eb90cac31