review: put the character on the floor, split the cubes, commit the shots

The review floor was a 5 cm slab centred 50 cm down, so the character floated
1.8 m above it. The floor is now 90 m x 90 m x 10 cm with its top face at Z 0 and
the character measures Z 0..83 cm - feet on the plane.

Two cubes only: A on the ground as the contact/scale reference, B held at 2 m so
its cast shadow separates from the body for comparison. The scale-cubes camera
was still aimed at the old three-cube row and now looks at both from the south.

Screenshots are committed per the owner's instruction, and .gitignore no longer
excludes them.

MEMORY.md

@@ -98,10 +98,10 @@ Scope: facts and traps that cost time to establish. Planned work lives in [ROADM
 
 ## 2026-11-07 — Hero facade build and review cameras
 
-- **The review floor is the only ground in the scene, and it is small.** Cameras 25 m from the building line look past its edge and see the black horizon band under the facade. Place facade cameras so both the facade and enough floor are in frame, or extend the floor.
+- **The review floor was 5 cm thick and centred at Z -50 cm**, so anything placed at Z 0 floated ~1.8 m. It is now a 90 m x 90 m x 10 cm slab with its top face at Z 0; a character's bounds should read Z 0..83 cm when it stands on it. **The review floor is the only ground in the scene.** Cameras 25 m from the building line look past its edge and see the black horizon band under the facade. Place facade cameras so both the facade and enough floor are in frame, or extend the floor.
 - **The facade's frontage faces Unreal -Y.** The FBX preset maps Blender +Y (north) to Unreal -Y, so the elevation looks at negative Y and a straight-on camera must stand at **Y < -1450 cm**. A camera at positive Y looks at the back wall; cameras inside Y -1443..+250 are inside the building and render flat blue.
 - **The imported mesh is centre-origin in X but not in Y or Z.** Bounds are `x -1302..1302, y -7..1250, z 0..1450` cm, so to put the front plane on the building line the actor goes at `Y = line + 7 cm`, and `X = east edge + half width`.
 - **`save_map` returns False, without an error, when the packed `.umap` is read-only.** The review map silently keeps its old camera list. `chmod u+w` the file before rebuilding; a `umap` that keeps rendering four shots after a sixth was added is this, not a caching problem.
 - **`StaticMaterial` is a struct**: `material.get_editor_property("material_interface")`, no `get_name()` on the wrapper.
-- **Screenshot PNGs must stay out of git.** They were committed once despite the AGENTS rule; `.gitignore` now carries `/Screenshots/` with a `!/Screenshots/README.md` exception.
+- **Review screenshots are committed on the owner's instruction (2026-11-07).** They are large PNGs, so a review run adds weight to the repo; keep the shot list short and delete retired shots rather than accumulating.