docs(devlog): back 020's withdrawal with the horizontal measurement (#2911)

* docs(devlog): back 020's withdrawal with the horizontal measurement

The file carried a WITHDRAWN banner and then, three lines later, a full "##
Change" section prescribing a rewrite of both dashboard grids from
repeat(auto-fit, ...) to a hard-coded two-up, plus an "## Acceptance" section
demanding no 0px track. A maintainer reading top-down got "nothing here ships"
followed by a complete diff to apply.

Worse, the withdrawal rested on an unmeasured claim. "The trailing gap measures
0, so nothing shifts today" was the whole reason to withdraw, and the axis it
concerns is the horizontal one the original request named first. Nothing in the
landed record backed it.

Measured now, by auditing the rendered edges of each grid's direct children
rather than reading the computed track list:

  vw     widths      topSpread  botSpread  gutters
  1600   556 / 556   0.0px      0.0px      one 16px
  1440   555 / 555   0.0px      0.0px      one 16px
  1280   475 / 475   0.0px      0.0px      one 16px
  1100   385 / 385   0.0px      0.0px      one 16px
  1024   347 / 347   0.0px      0.0px      one 16px

Identical widths, shared top and bottom edges, exactly one gutter, no trailing
gap after the second card. The collapsed third track displaces nothing on either
axis in either grid, so there is no horizontal misalignment here and the
generated-but-collapsed track is not a defect.

The rewrite is kept as a named rejected option rather than deleted: it fixes
nothing measurable today and would trade auto-fit's automatic behaviour for a
count that a third card would have to come back and change. The note says
plainly that it did not ship and is not recommended, and points at the audit as
the procedure to re-run if a third card ever lands.

Documentation only; no stylesheet is touched.

* docs(devlog): anchor 030's citations to selectors, not drifted lines

Two defects in the landed file, both verified against origin/dev rather than
assumed.

The banner said "Implemented by this pull request". That was true while #2906 was
open and is meaningless on dev, where a reader cannot tell which PR it means. It
now names #2906 and 4d646c4.

Every line number it cited had drifted, and the cause is the fix the document
itself describes: that change inserted lines above the rules being cited. Read
straight off origin/dev:

  cited                     actually there now
  styles.css:2003           min-width: 220px        (.logs-table-wrap is 2011)
  styles.css:755            the cap line INSIDE .action-toast (rule is 749)
  styles.css:1222           z-index: var(--z-modal) (.notice is 1215)
  styles.css:2198 (dvh)     background: var(--glass-rail) (drawer is 2213)

So a maintainer following any citation landed on unrelated CSS. Renumbering would
just re-arm the same trap on the next insertion, so the rules are now named by
selector with the line as a hint, and the banner says why.

Documentation only; no stylesheet is touched.

Author: lidge-jun

devlog/_plan/260829_gui_dashboard_slop/020_phantom_grid_track.md

@@ -21,28 +21,41 @@ container is wide enough to nominally fit it. With only two children the track
 collapses to 0 and the trailing gap measures 0, so nothing shifts today. It
 becomes a real phantom gap the moment a third card is added.
 
-## Change
-
-Both grids hold a *known* number of cards, so express that instead of asking
-`auto-fit` to guess:
-
-```css
-grid-template-columns: repeat(auto-fit, minmax(min(100%, 21rem), 1fr));
-```
-
-becomes an explicit two-up that collapses to one column by container width:
-
-```css
-grid-template-columns: 1fr;                 /* narrow: stack */
-@container / min-width: two-up → 1fr 1fr    /* wide: matched pair */
-```
-
-Applies to `.dash-sidecar-grid` and `.dash-overview-tools`. The wrap width stays
-`21rem` per card so the responsive behaviour is unchanged — verified by the same
-sweep, which must keep reporting STACKED at 900/430 and PAIRED at 1024+.
-
-## Acceptance
-
-- No `0px` track in either grid's computed columns at any swept width.
-- The PAIRED/STACKED pattern per width matches the baseline exactly (no
-  behavioural change, only the phantom track removed).
+## Why this was withdrawn — measured
+
+The claim above ("the trailing gap measures 0, so nothing shifts today") was the
+reason to withdraw, but it went unmeasured on the axis the request named first —
+the horizontal one. It has now been measured, by auditing the rendered edges of
+each grid's direct children rather than reading the computed track list.
+
+`.dash-sidecar-grid` and `.dash-overview-tools`, two-up regime:
+
+| vw | card widths | top spread | bottom spread | gutters |
+|----|-------------|-----------|---------------|---------|
+| 1600 | 556 / 556 | 0.0px | 0.0px | one 16px |
+| 1440 | 555 / 555 | 0.0px | 0.0px | one 16px |
+| 1280 | 475 / 475 | 0.0px | 0.0px | one 16px |
+| 1100 | 385 / 385 | 0.0px | 0.0px | one 16px |
+| 1024 | 347 / 347 | 0.0px | 0.0px | one 16px |
+
+Identical widths, shared top and bottom edges, and exactly one gutter — no
+trailing gap after the second card at any width. The collapsed third track
+consumes no space and displaces nothing, in either grid, on both axes. So there
+is no horizontal misalignment to fix here, and the generated-but-collapsed track
+is not a defect.
+
+## The rewrite that was considered and rejected
+
+Recorded so it is not mistaken for a pending plan: **none of this shipped, and
+applying it is not recommended.**
+
+The option was to stop asking `auto-fit` to guess and state the known card count
+— `grid-template-columns: 1fr` with a container query promoting to `1fr 1fr` —
+for both grids. It was rejected on cost against benefit: it fixes nothing
+measurable today (see the table above), and it trades `auto-fit`'s automatic
+behaviour for a hard-coded count, so a third card would then need a stylesheet
+change instead of just appearing. The phantom track only becomes real if a third
+card is added, and at that point `auto-fit` is what handles it correctly.
+
+If a future change does add a third card to either grid, re-measure the trailing
+gap first; the audit above is the procedure.

devlog/_plan/260829_gui_dashboard_slop/030_dynamic_viewport_units.md

@@ -1,25 +1,29 @@
 # 030 — Dynamic viewport units in scroll surfaces (wp3)
 
-> **Implemented by this pull request**, separately from the sidecar alignment fix
-> that the rest of this unit records. It is a different change to a different
-> file (`gui/src/styles.css`), kept in the same unit because one audit pass found
-> both.
+> **Shipped in #2906** (`4d646c494`), separately from the sidecar alignment fix in
+> #2905 that the rest of this unit records. It is a different change to a
+> different file (`gui/src/styles.css`), kept in the same unit because one audit
+> pass found both.
+>
+> Rules below are named by selector, not line number: the fix this document
+> describes inserted lines above the very rules it cites, so the original
+> citations (`styles.css:2003`, `:755`, `:1222`) now land on unrelated CSS.
 
 ## Defect
 
-`gui/src/styles.css:2003`:
+`.logs-table-wrap` in `gui/src/styles.css` (line 2011 as shipped):
 
 ```css
 .logs-table-wrap { max-height: calc(100vh - 260px); }
 ```
 
 `vh` is the *large* viewport: it ignores mobile browser chrome, so the log table
 is capped for a viewport taller than the one the user can see, pushing the last
-rows under the browser UI. The rest of the shell already moved to `100dvh`
-(styles.css:244, 247, 411, 412, 2198), so this line is an outlier, not a
-convention.
+rows under the browser UI. The rest of the shell already moved to `100dvh` —
+`.app` (244), the sidebar (247), `.main-inner--combos` (411-412) and the mobile
+drawer (2213) — so this line is an outlier, not a convention.
 
-`styles.css:755` and `1222` cap toast width with `calc(100vw - Npx)`. Per CSS
+`.action-toast` (749) and `.notice` (1215) cap toast width with `calc(100vw - Npx)`. Per CSS
 Values and Units 4, `100vw` includes the classic scrollbar gutter, so a
 scrollbar-reserving platform can in principle render a cap wider than the visible
 area.
@@ -37,7 +41,7 @@ file at equal specificity, so source order won and the toast resolved to 70ch
   classes so it beats the later `.notice` rule. Both halves of the cap are
   restated: dropping the viewport term let the toast reach the screen edge at
   430px (measured `left = 0`, losing the 24px inset the right side keeps).
-- `styles.css:2003` is the only static `vh` in a scroll surface; the `12vh`
+- `.logs-table-wrap` was the only static `vh` in a scroll surface; the `12vh`
   padding on the toast wrapper is decorative offset, not a size cap, and stays.
 
 ### Not changed: the `vw` → containing-block rewrite