docs: the readouts strip hides when empty

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

docs/claude/verification.md

@@ -438,9 +438,9 @@ precedent, not an exception.
 - `UDPSCOPE_PROBE_CURSORS_MS` and `UDPSCOPE_PROBE_MEASURES_MS` also print the dock's copy of what they read:
   a `dock cursors:` line after every `[cursors-probe]` report and a `dock measures:` line at the
   measures probe's added / settled / final stops, each with a `strip:` line beside it (the readouts strip,
-  shown when `!dock_shown || collapsed`; `expected=` is that, `visible_ok=1` that the strip agrees); each probe
+  shown when `(!dock_shown || collapsed)` and the cursors are on or there is a measurement; `expected=` is that, `visible_ok=1` that the strip agrees, `groups=`/`groups_ok=1` the same for its Cursors / Measures groups and separator; the measures probe's `start` line, before it adds anything, is the hidden "neither" state -- run it from a fresh config); each probe
   ends by hiding the dock for 0.6 s and reading the strip (`dock hidden`, `dock restored`: under xvfb the
-  window is collapsed, so `visible=1 expected=1 h=26 same_text=1` on both). **`same_text=1` on every one** is the assertion that the
+  window is collapsed, so `visible=1 expected=1 h=26 same_text=1` on both, given something to read). **`same_text=1` on every one** is the assertion that the
   dock, the strip and the page show one string; `fits=1` that the Readouts box is no wider than the dock. Entries in
   `probe-readings.md`. The exit chain also prints one `[readouts]` line (pages registered, the dock page's three
   children, the dock's width, the pages' sensitivity, whether the stream has signals) on every exit-dump run.