Overhaul the head source: weld + relax the decimated MakeHuman head into one clean manifold shell

docs/screens/head-review/README.md

@@ -15,7 +15,11 @@ clearer silhouette.
 | | Source | Tris (head) | Read |
 | --- | --- | --- | --- |
 | **Before** | procedural `_face` (sphere + primitives) | ~1,900 | flat face, slit eyes |
-| **After** | MakeHuman head + project eyes/brows/mouth | ~2,180 | nose/chin/jaw landmarks |
+| **After** | overhauled MakeHuman head + project eyes/brows/mouth | ~1,880 | smooth nose/chin/jaw landmarks |
+
+The head source was overhauled 2026-11-04: the blocky decimated MakeHuman head was welded
+(merge-by-distance) and Laplacian-relaxed into one clean manifold shell (`makehuman_head.glb`,
+1,548 tris skin), then the project eyes/brows/mouth were added.
 
 ## AI-generated target concept
 
@@ -45,6 +49,8 @@ Left to right: front, three-quarter, profile.
 1. The hair cap still reads as a stepped block instead of hugging the skull.
 2. The brows weld to the face but can read as a slightly separate bar.
 3. The neck underside cap is plain; it is hidden by the body neck in the assembled character.
+4. The head skin is 1.5k tris (smooth but low-poly); a retopology pass could add resolution if a
+   portrait shows faceting.
 
 ## Decision needed