detail.step/tip.step now read "第 s 步 (共 n 步)" / "Turn t · Step s of n" —
the same per-turn tally a turn-mode bar's stepCount carries, so step and
turn granularities agree on how busy a turn was. A shared turnStepsOf()
getter feeds the trend tooltip, the detail head, the files scope label,
and the browser picker/meta rows.