final review fixes: reject inf plot width, nearest-cell distance in double, tour wording

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docs/claude/probe-readings.md

@@ -424,7 +424,7 @@ Two lines of the self-check output are assertions in disguise:
   the group, because `hold_pinned_window()` prefers a member that has moved since `pinned_stated_`
   — that is how it tells a gesture from its own echo — so a fit that wrote the group alone reads
   back as the zoomed range one frame later.
-- `[layout-probe] <action> rows=N buttons=B done=D done_box=[x,y,WxH] rows_y=[..] close=[..] add=[..] traces=[..] cells=[..] colweights=[..]`
+- `[layout-probe] <action> rows=N buttons=B done=D done_box=[x,y,WxH] rows_y=[..] close=[..] add=[..] resize=[..] traces=[..] side_w=S cells=[..] colweights=[..]`
   `side_w` is the sidebar column's width and **must be its own request (280), never 0**: it read 0 while
   the divider sat at the window's right edge, which is a panel that is not there. It was 280 during the
   first frames and 0 once the window had settled, so read it from a `placed` line rather than the first.