feat(vehicle): the car renders, built from the owner's hot hatch template

The invisible-vehicle defect is closed. Shot 9 now shows the car instead of an empty road.

Tools/vehicle_from_template.py converts Art/blender/vehicle/hot hatch.blend into UE-ready
assets, following two skills:

  vehicle-artist - systems split (body 113k tris, trim 10.5k, glass 20.5k, lights 18.6k,
  wheels 47.8k), one UCX_ hull 1.45 x 3.94 x 0.76 m, two decimated LODs at 39.7k and 13.6k.
  unreal-export - scale normalised to a documented 4.05 m hot hatch before export (the
  template measures 7.26 m, factor 0.5579), then verified after import: body bounds
  1.51 x 4.02 x 1.22 m against the 4.05 m target.

Staged as five plain StaticMeshActors, because the earlier probe proved those render while
the same meshes attached to the vehicle pawn do not.

Open and recorded rather than hidden: judge_screenshot returns verdict=no confidence=0.9 -
the silhouette does not read as a hot hatch from this angle and the car floats slightly.
The likely causes are a system misclassification in the template conversion and an
origin-height error of a few centimetres.

Tools/ue_build_review_map.py

@@ -292,7 +292,7 @@ try:
             # The sedan, staged on the carriageway at (-12950, -900). Three-quarter front
             # view from the road so both the body and the wheels are visible: a side-on
             # or rear view hides the wheel stances that the build is judged on.
-            ("demo-vehicle", unreal.Vector(-12250, -1600, 620), unreal.Vector(-12950, -900, 430), 50.0),
+            ("demo-vehicle", unreal.Vector(-12560, -1560, 560), unreal.Vector(-12950, -900, 420), 45.0),
             ("demo-spawn-view", unreal.Vector(-13336, -3100, 620), unreal.Vector(-13336, 1300, 620), 48.0),
             # Street level, from the north sidewalk: the old camera sat at Y -400,
             # inside the facade body (which spans Y -1457..-200), so it looked at