docs: record the round 5 review pass, evidence and test results

docs/redesign/round5.md

@@ -143,3 +143,209 @@ preview build on a headed GPU Chromium. They are in `docs/redesign/round5/`.
   | --- | --- | --- | --- | --- | --- |
   | Before | 70.1 | 82.6 | 83.8 | 81.8 | 87.2 |
   | After | 68.7 | 83.5 | 79.7 | 83.7 | 95.1 |
+
+## Design review pass (Fable)
+
+A design consultant reviewed the first pass. Its calls were adopted, except
+where noted under "Deviations". Evidence is in `docs/redesign/round5/`.
+
+### The sign interlude (items 5, 6)
+
+- **Sequence.**
+  - The reading plates step aside: 260 ms in-quart, rising 24 px. Headings
+    fade only.
+  - The road and the sign then have the frame to themselves. The sign
+    hangs from a 3D gantry truss, about 600 px wide in the upper third.
+  - It lifts off the truss and arcs into the window, landing within 2 px
+    (unit tested). The truss passes overhead as it docks.
+  - The plates rise back with a 90 ms stagger (720 ms out-expo).
+  - The whole sequence is driven by `html[data-interlude]` (`on`, then
+    `rise`), which the scene loop owns.
+- **Window.**
+  - At 1280 px and wider it is 320x72, with an 8 px bulge in the beam.
+  - The rails sit at 40%.
+  - An amber cone of light falls below the window.
+- **Docked.**
+  - The 3D face hands off in 200 ms to a flat 2D plate. The plate mirrors
+    the face: tab, label fitted like the canvas, and lane rule. So the
+    handoff lands in place (`window-handoff-1440.webp`).
+  - Hover brings back the 3D twin, which leans at most about 4 degrees,
+    with a "DRIVE TO EXIT NN →" label (`window-hover-1440.webp`).
+- **Skips.**
+  - Fast scrolling: brisk latches skip the interlude.
+  - A hash load or back/forward lands docked without replaying.
+  - Reduced motion: no scene and no interlude. The plates simply change.
+- **Measured at 1440 (nav click).**
+  - Plates hidden from 340 to 1246 ms, rise until 2355 ms, idle at 3388 ms.
+  - About 1.9 s with the rise, against the brief's ~1.4 s. This was kept
+    so the arc stays readable.
+  - A wheel crossing triggers the interlude.
+  - A 2500 px jump shows no sign.
+
+### Top bar and controls (items 4, 8)
+
+- **Layout.** Brand | exits 01–04 | window | exits 05–08 | bay.
+- **Window plate.**
+  - It shows the current exit tab in the sign colour, the chapter, a route
+    rule, and a chevron breathing at 0.5 Hz.
+  - At the destination the chevron reads "AGAIN ↺", and the window drives
+    back to the start.
+- **Exit lamps.**
+  - The current exit lamp carries an 18 px ghost swatch in the sign colour.
+  - The NEXT EXIT plaques and the RESUME chip are retired. Resume now lives
+    in the window ("RESUME EXIT NN →").
+- **Bay.**
+  - Two lilac tiles: the soundtrack, with a three-bar equaliser that moves
+    at most 1 Hz while playing, and settings.
+  - Settings opens a popover: 240 ms out-expo, Esc closes it, focus is
+    trapped, and it becomes a bottom sheet on phones. Volume and Pause
+    motion moved into it.
+  - The active state is amber.
+  - Tooltips hang from the button's right edge, are hidden while a popover
+    is open or on touch, and are kept out of the accessible name.
+- **Title stack.** The chapter title is smaller (5.6vw, up to 100 px), with
+  a tighter gap, so the body starts about 50 px higher at 1440.
+
+### Cards (items 9, 10)
+
+- **One rule.** A single `.plate` with panel, record and grid variants.
+- **Motion.**
+  - Arrivals ease out-expo, departures in-quart.
+  - Durations are 160, 320 and 720 ms.
+- **Entrance.** A 28 px rise plus a top-down `clip-path` unmask over
+  `view()` entry 0–55%. Firefox and other browsers without
+  `animation-timeline` get an IntersectionObserver fallback
+  (`useCardEntrances`).
+- **Why `translate`.** Entrances animate `translate`, not `transform`. A
+  filled animation overrides `transform`, which had silently disabled the
+  hover lift.
+- **Focus.** Focus-visible gets the hover accent edge plus an outline.
+- **chapter-settle removed.** It is dropped because the interlude now owns
+  the chapter change ("one timeline owns the chapter change").
+
+### Outro: Engine off (item 1)
+
+- **Car and scene.** On arrival the drive winds down to a stop: travel,
+  traffic and wheel spin. The tail and running lamps drop to parking level,
+  the sky darkens 10%, stars rise about 80%, and the grid fades.
+- **Sound.** The engine and road noise take a 1.2 s low-pass sweep to idle
+  when the final exit is reached. Driving away restores them.
+- **Letterbox.**
+  - Each bar stays within 8vh.
+  - The credit, built from real identity facts, types into the lower bar
+    in mono. It cannot go in the upper bar, which the contact avatar
+    shares.
+  - The Email CTA and the END OF ROUTE plaque stay clear at 1440 and 390.
+- **Reduced motion.** Bars and poster dimming only; the credit simply
+  appears.
+
+### Found on the way
+
+- **The mouse wheel did not scroll at all.**
+  - Cause: `overscroll-behavior: none` on the script-scrolled,
+    overflow-hidden reading viewport, introduced in 71959f7, swallowed
+    wheel events.
+  - Removed. The wheel now scrolls and wheel crossings raise signs.
+- **The docked plate's root was a fragment.** A template comment made it
+  one, which dropped `aria-hidden` from the HUD in tests. The comment was
+  moved into the script.
+- **Grey slabs on the road.** These are the existing Blender district
+  billboards and gantries, not the new truss. They were left as authored.
+
+### Deviations from the review
+
+- **Bay targets.** The buttons stay 44 px targets with a 36 px drawn tile.
+  The keyboard and pointer-target tests require 44x44.
+- **A third recovery button.** It stays in the bay while motion is paused
+  or static ("Enable motion"). Reduced-motion users must reach it without
+  opening settings.
+- **Interlude length.** It runs about 1.9 s rather than 1.4 s; see above.
+- **The 2D crossfade under reduced motion.** It is a plain swap: with
+  reduced motion the scene never starts, so there is no 3D sign to
+  crossfade from.
+
+### Risks checked
+
+- **mask-composite with backdrop-filter:** no backdrop-filter is used
+  anywhere.
+- **No `animation-timeline` (Firefox):** covered by the IntersectionObserver
+  fallback.
+- **will-change:** none added.
+- **Scene cost:** the engine-off and interlude scene work is uniform writes
+  only. It is free on every tier.
+- **Adaptive tiers:** the low tier keeps the CSS bars and plates.
+
+### Verification after the review pass
+
+- **Title stack (1440x900, Experience).** Below the 72 px beam, the section
+  starts at 100 px, the h2 at 148–245 px, and the chapter body at 268 px.
+  Evidence: `round5/title-stack-1440.webp`.
+- **Interlude sequencing.** A CDP screencast of a Start → Experience click
+  showed the Profile chapter flashing past during the smooth scroll, before
+  the sign's approach hid the plates. A long navigator jump (more than 0.6
+  viewport) now pre-arms `data-interlude="on"` at click time, while the
+  scene runs. The loop takes the attribute over when the interlude starts,
+  and a 1.4 s timeout lets the plates rise if no interlude follows.
+  Evidence: `round5/interlude-prearm-1440-sequence.webp`.
+- **Found by the browser suite.**
+  - The volume `<output>` was an implicit second live region. It is now an
+    `aria-hidden` readout, and the slider carries `aria-valuetext`.
+  - The bay tiles lost their outline in forced colours, because the
+    gradients are dropped. They now get a `ButtonText` border.
+
+### Playwright against the round-4 baseline
+
+The baseline is 63 failures. The final full run gave 147 passed, 88
+failed and 55 skipped. Of the 27 failures new against the baseline, 25
+were coupled or fixed and re-run:
+
+- **Coupled to Volume and Pause moving into settings:** audio-controls
+  ×3, bfcache, scene-controls and visual-regression audio. These tests
+  were updated.
+- **Coupled to the gantry:** title-navigation ×2, and journey-integration
+  ×4, where the window pre-draws the resting "Start" twin. These tests
+  were updated.
+- **Real regressions, fixed:** forced colours (bay borders) and the
+  scene-controls status (the `<output>` live region).
+- **Flaky under full-suite load:** contact-refinements reading mask. It
+  passes on a re-run.
+
+Two remain on both projects and were left as is:
+
+- journey-integration "carries a departed sign past the car"
+- journey-integration "keeps the readable Profile face outside its
+  destination panel"
+
+Both assert the retired roadside choreography: the sign now hands off to
+the window plate. Seven siblings already fail in the baseline. Rewriting
+the geometry oracle is out of scope.
+
+Fixed against the baseline: accessibility-keyboard "explicit keyboard
+navigation" (desktop) and audio-controls compact panels (mobile).
+
+### Test edits (intentional behaviour changes)
+
+- **Unit, `tests/unit/sign-rendering.test.ts`.**
+  - The fade test now uses relative texture counts, and the docked face
+    is hidden after the handoff.
+  - "closes in over the road in the upper third, then arcs up into the
+    window".
+  - "leaves the window to the flat plate as it departs".
+  - The tilt applies only on hover.
+- **Unit, `tests/unit/SceneCanvas.test.ts`.** Volume and Pause motion are
+  checked inside the open settings panel.
+- **Browser, settings.**
+  - `audio-controls.spec.ts`: opens Drive settings for volume and pause.
+    The volume stays visible beside Quality after Static. The interruption
+    test lifts its synthetic state before Resume, because Resume and Mute
+    now share one slot.
+  - `bfcache-lifecycle.spec.ts`, `scene-controls.spec.ts` and
+    `visual-regression.spec.ts`: open Drive settings before Pause motion
+    or volume.
+  - `tests/performance/drive-trace.spec.ts`: Drive settings instead of
+    Sound volume. Not run.
+- **Browser, gantry.**
+  - `title-navigation.spec.ts`: the gantry is docked and unscaled from the
+    first frame. The current exit is its lane lamp or a rounded inset.
+  - `journey-integration.spec.ts`: `roadsideLabels()` leaves out the
+    resting "Start" twin texture from the roadside label checks.