docs: the readouts strip

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

docs/claude/probe-readings.md

@@ -1842,6 +1842,24 @@ These ride on the `[cursors-probe]` readings (every state line gets a `dock curs
 - **`dock_sensitive=1`** (cursors only): the dock's cursor grid is live whenever the stream has signals; `0` before them ("disable, do not hide"), `0` with signals is the dock never coming back.
 - On a session with no cursors line, or with no measurements, `lines=0 page_lines=0 same_text=1` is correct: the dock then shows `no measurements` for the measurements (one non-value label, not counted in `lines`).
 
+## `strip:` (the readouts strip)
+
+```
+[cursors-probe]  <what> strip: visible=0 dock_shown=1 cursors=4 measures=0  same_text=1 h=0  sens_same=1 collapsed=1 window=756
+[measures-probe] <what> strip: visible=0 dock_shown=1 cursors=0 measures=12 same_text=1 h=0  sens_same=1 collapsed=1 window=756
+[cursors-probe]  dock hidden strip: visible=1 dock_shown=0 cursors=4 measures=0 same_text=1 h=26 sens_same=1 ...
+[cursors-probe]  dock restored strip: visible=0 dock_shown=1 ...
+```
+
+One `strip:` line follows every `dock cursors:` / `dock measures:` line, and each probe ends with a drive that puts the dock away through the wish (`sidebar_wanted = false`), reads the strip 600 ms later (`dock hidden`), restores the wish and reads again (`dock restored`).
+
+- **`visible` is the opposite of `dock_shown`** (`dock_shown` is `show-sidebar`) on every settled line. `visible=0 dock_shown=0` or `visible=1 dock_shown=1` is `sync_readouts_strip()` not run (or run before the reconciliation); a single such line right after the probe's own `update_side_visibility()` is the sub-frame before the next tick and not a defect.
+- **`h` is 26 with `visible=1`, 0 with `visible=0`.** Any other visible height is the chips setting the strip's height (the button trim in `ui_widgets.cpp` or the `height-request` lost).
+- **`same_text=1` is the assertion**: every strip label (the cursors' `who` and delta, the measurements' values) has the dock's text, and the counts of chips match the dock's lines. `0` is a value written to one view only -- a dock cell set without `dock_cursor_cell()` / `dock_measure_value()`, or a rebuild that did not mirror.
+- **`cursors` / `measures`** are the chip counts and equal the dock's `lines`.
+- **`sens_same=1`**: the strip's cursor chips and the dock's cursor grid have the same sensitivity (`dock_set_cursors_sensitive()`).
+- **`collapsed=1 window=756`** on every line under `xvfb-run`: the window is below the 900 px `kSidebarRoom`, so these lines are all the *collapsed* case (a wished dock stays overlaid, `visible=0`; a hidden one shows the strip). The non-collapsed case is not reachable from a probe, because a window with no manager cannot be resized by `gtk_window_set_default_size()`. The very first line can read `collapsed=0` (the tick has not set it yet).
+
 ## `[sidebar-probe]`
 
 ```