Record the seed 946 deferral and the fuzzer results at 3091fb8

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

docs/HANDOFF.md

@@ -14,18 +14,23 @@ detached comparison checkout is `/home/bob/repos/iris-layout-baseline`. It is
 the reviewed baseline this work must preserve or improve.
 
 The continuation is `/home/bob/repos/iris-layout-experiment`, now on branch
-**`wip/one-ask`** at **`3091fb8`**, one commit over `4328eac` (the head of
+**`wip/one-ask`** at **`0ef87eb`**, two commits over `4328eac` (the head of
 `wip/transparent-frames`, which is unchanged). It replaces the step 3 plan
-below with a smaller protocol change, and it passes every fast check:
+below with a smaller protocol change, and it passes every check that has
+finished:
 
-| check at `3091fb8` | result |
+| check at `0ef87eb` | result |
 | --- | --- |
 | `cargo fmt --all --check`, clippy `-D warnings`, with and without `layout-diagnostics` | clean |
-| `cargo test --workspace` (debug) | 114 suite, 20 core, 11 generated, all green |
-| the two decided-box pins from step 1 | **pass** (red at `4328eac`) |
+| `cargo test --workspace` (debug) | 115 suite, 20 core, 11 generated, all green |
+| the two decided-box pins from step 1, and the new seed 946 pin | **pass** (the first two were red at `4328eac`) |
 | `cargo test --release --test generated` | 11/11 |
 | shrinker, 400 seeds, depth 5, all fifteen cases | agree, 56 s |
-| 1000 seeds at depth 6, and the 2000-seed depth-4 scan | see `docs/LAYOUT_LOG.md`; they were running when this was written |
+| 2000-seed depth-4 scan, all fifteen cases | agreed at `3091fb8` (269 s); rerun at `0ef87eb` was running when this was written |
+| 1000 seeds at depth 6 | found seed 946 at `3091fb8`, fixed and pinned in `0ef87eb`; rerun was running when this was written |
+
+Read `/tmp/oracle-1000-6b.log` and `/tmp/shrink-2000-4b.log` for the reruns
+if they still exist; otherwise run them (step 1).
 
 The worker's uncommitted step 3/4 experiment is preserved as branch
 `wip/step3-experiment` (one commit over `4328eac`) and as
@@ -156,6 +161,15 @@ back at the retained place of the box the parent's answer *chose*. Both halves
 are needed: seed 2 at depth 4 (a stack sized by its text) fails without the
 second.
 
+A widget its parent asked more than once in one draw -- a share child, asked
+in the room and then in its slot -- has two questions and one record, so it
+cannot settle locally: `redraw` defers it to the parent the way it defers a
+widget whose declared length changed (`ActiveData::re_asked`, set by
+`widget_at` when the child is already in `children`). Seed 946 at depth 6
+found the case: a fixed-height column that is a share while its rect fits
+and a fixed width once it does not, so emptying it changes the room answer
+and not the slot answer.
+
 A symbolic length a child pinned now composes through `Part::Of` where the
 part is the whole box less pixels, and pins the parent's own length otherwise
 (`in_parent`). Dropping it let a zero `Pad` reuse a drawing across a narrowed
@@ -267,18 +281,18 @@ the probe's diff readable; do this as one mechanical commit. Suite, oracle.
 Work counters at `3091fb8`, seed 1 and 13, depth 8, widget draws / distinct
 widgets, beside `e44dea3` (#18) and `49cec82` (the branch head before this):
 
-| seed 1  | e44dea3 | 49cec82 | 3091fb8 |
+| seed 1  | e44dea3 | 49cec82 | 0ef87eb |
 | ---     | ---     | ---     | ---     |
 | cold    | 369/261 | 516/288 | 331/288 |
-| many    | 157/95  | 187/119 | 78/78   |
+| many    | 157/95  | 187/119 | 110/92  |
 | size    | 16/12   | 3/3     | 3/3     |
 | scroll  | 2       | 1       | 1       |
 | resize  | 13/13   | 24/76   | 40/15   |
 
-| seed 13 | e44dea3  | 49cec82  | 3091fb8  |
+| seed 13 | e44dea3  | 49cec82  | 0ef87eb  |
 | ---     | ---      | ---      | ---      |
 | cold    | 1330/707 | 2940/982 | 1179/982 |
-| many    | 524/159  | 1091/423 | 335/333  |
+| many    | 524/159  | 1091/423 | 424/364  |
 | resize  | nothing  | 2215/510 | nothing  |
 
 `many` and `size` are better than #18 at seed 1 and `many` draws fewer times
@@ -287,13 +301,17 @@ at seed 1 draws 40 times where #18 drew 13. Two mechanisms, both understood:
 
 - **A share child is asked twice per span draw** -- in the measuring room
   with the frame forwarded, then in its slot with the frame narrowed. Each
-  ask that reads pixels or pins a length draws. Give `Span` a measure-only
-  ask for the first pass: reuse the retained *answer* when its holds contain
-  the room, without validating or relocating the drawing, and let the
-  placing ask settle the drawing. The answer contract must then carry no
-  symbolic pin (a span's total does not depend on `far`; only its slots do),
-  which is the separation the worker's experiment made with
-  `answer_extent_len`. Measure `many` at seed 13 before and after.
+  ask that reads pixels or pins a length draws, and since `0ef87eb` every
+  local change inside a share child redraws its span as well. Give `Span` a
+  measure-only ask for the first pass: reuse the retained *answer* when its
+  holds contain the room, without validating or relocating the drawing, and
+  let the placing ask settle the drawing. The answer contract must then
+  carry no symbolic pin (a span's total does not depend on `far`; only its
+  slots do), which is the separation the worker's experiment made with
+  `answer_extent_len`. With that, a twice-asked child could keep both
+  answers and settle locally by re-asking both questions instead of
+  deferring. Measure `many` at seed 13 before and after; the seed 946 pin
+  must stay green throughout.
 - **A positive-direction span with no shares pins `far`** it does not need,
   so a resize redraws it. Read `extent_len` only where a slot depends on it
   (shares, or `Sign::Neg`), and express the measuring room's far end without