Audit prop budgets and add a prop-gallery art check

- audit_glb decodes geometry: 400 tris / 600 verts budget, degenerate
  triangles, UV range, ground contact, one material; newspaper box parts moved
  to sit on y=0
- capture_prop_gallery.gd renders the six props on a studio backdrop; new
  prop_gallery catalogue entry + AI mockup (compare 10 good, judge match 0.90)
- headless test that instances share the imported atlas material
- README documents the gallery capture and budget; TODO props pipeline section
  moved to DONE

MEMORY.md

@@ -52,6 +52,9 @@ Session memory for durable decisions, state, and gotchas. Keep concise, remove o
   flat plane, so avoidance (not a baked mesh) routes guests around props. Placements live in
   `PROP_PLACEMENTS` with `placement_problems()` validation; variants come from `variant_for(index)`.
   `smoke_props.gd` must be windowed because the guard reads captured-mouse input.
+- **Prop pipeline (done):** audit enforces 400 tris / 600 verts, ground contact, UV range, no
+  degenerate tris, one material. `capture_prop_gallery.gd` writes `10-prop-gallery.png` (3x2 studio
+  line-up, back row on a platform) and the `prop_gallery` catalogue entry compares it.
 - **Presentation pass remaining (TODO):** NPC characters and player movement. Grounding facts: the
   NPC rig is rigid capsules with a whole-limb swing, and `guard_controller.gd` uses one `accel`
   value. Each task should get its own windowed smoke or capture where it changes feel/looks.