fix: polish hygiene backlight and origin accessory heroes

[TMHSDigital]

Summary

• mesh-hygiene-audit: remove the in-frame emissive HoleCard; backlight the through-hole with an out-of-frame POINT light so the aperture still reads without a clipped light panel (Layer 1). Same brass DIRTY/CLEAN; audit-derived bead/edge markers kept (emission tuned down).
• prop-origin-transform: rebuild flanged conduit + deep shadowed socket; drop orange/blue emissive blobs; same metal fitting both sides so displacement carries the proof; closer framing with clear margins.

What failed (#103 follow-up)

• Hygiene: HoleCard was a hard-edged emissive plane that clipped and read as an undressed light shape.
• Origin: TRAP accessory read as floating blue/orange blobs; empty socket not card-legible.

Visual-pass log

mesh-hygiene-audit — 6 iterations

1. AREA HoleBack still cast a hard rectangular pool / clipped whites
   2–3. Soften emission; still slab-like floor pool from AREA
2. Switch to out-of-frame POINT; pull key/glint; max luma ~0.98
   5–6. Widen framing so DIRTY base / CLEAN label clear edges

Contract (Pass 2): DIRTY through-hole + loose bead vs CLEAN solid, same brass.

prop-origin-transform — 6 iterations

1. Camera too tight (tops clipped); both sides looked seated
   2–3. Pull back; jump too small (~0.08) with small rot
   4–5. Larger prop rot → jump ~0.36–0.51; dark well materials; 3/4 camera
2. Fill nudge; placard margins

Contract (Pass 2): TRAP bare-parent part displaced off dark mount well vs KEEP flange seated.

Checks (unchanged closed forms)

• Hygiene: verts=66 edges=136 faces=72 volume=0.652001 on 5.1.2 and 4.5.11
• Origin: bare_jump=0.428275 mpi_err=2.980e-08 (no closed-form change; accessory mesh is render form)

Contact sheets

• docs/gallery/contact-sheets/mesh-hygiene-audit-contact-sheet.webp (hero mean luma 0.232)
• docs/gallery/contact-sheets/prop-origin-transform-contact-sheet.webp (hero mean luma 0.254)

Binaries

• .scratch/blender-5.1.2-windows-x64/blender.exe → 5.1.2
• .scratch/blender-4.5.11-windows-x64/blender.exe → 4.5.11 LTS

Evidence

• Live: check-only both binaries; EEVEE stills; build_gallery.py; Playwright gallery desktop+mobile
• Inspection: HTML alts; thumbnail socket legibility judgment

Test plan

• blender-smoke 4.5 + 5.1
• validate / drift / Socket