=== last 3 user asks across the whole branch ===
- Third ask.
- Fourth ask.
- Final pivot: do Z.

=== first user ask in the discarded span (chronological anchor) ===
"First ask."

=== budget summary ===
5 user messages total
8 discarded / 1 kept
≈ 43 discarded tokens
≈ 7 kept_tail tokens

=== latest user ask, single line, hard char cap ===
"Final pivot: do Z."