Fix the MPFB prototype neck and ankle junctions

TODO.md

@@ -203,24 +203,25 @@ owner reviews the silhouette and a production integration decision is recorded.
       apply the helper MASK, scale to 1.81 m, retarget the A-pose arms to the contract wrist
       (`x=±0.27`, `z=0.78`), cut the neck at 1.505, decimate, bisect the clothing boundaries, paint
       the five slots, add a short neck flare, project hands, rounded shoe shells, cuffs, the
-      accepted head and the 14-bone armature. Current output: **15,333 tris / 9,241 raw verts /
-      13,314 seam-split verts / 1.810 m / 14 bones / 10 materials**; `inspect` clean, feet grounded.
+      accepted head and the 14-bone armature. Current output: **15,373 tris / 13,552 glTF verts /
+      13,560 seam-split verts / 1.810 m / 14 bones / 10 materials**; `inspect` clean, feet grounded.
 - [x] Replace the spiky decimated MPFB hands with the project palm/finger primitives, straighten the
       splayed MPFB feet so the shoes point forward, and use rounded shoe shells + cuffs instead of
       flat blocks. Use flat slot colours in the prototype because the one-shot MPFB UV unwrap does
       not match the per-slot NPC atlases.
-- [ ] Owner reviews the current MPFB body renders (`tmp/npc-parts/mpfb_proto/renders55/`):
-      the head/hair read well, but the decimated neck stub is boxy where the accepted head sits on
-      it, the shoes are still block-shaped, the ankles are pencil-thin where they meet the shoe
-      shells, and the shirt hem forms a V at the crotch. Earlier collar/neck-blend attempts were
-      rejected (disk shelf, neck brace, sawtooth collar); the current build ships no collar.
-- [ ] Fix the neck junction before any rollout: either cap and taper the accepted head's open
-      bottom in `makehuman_head.glb` (rebuild the source, re-review the face) or insert a welded,
-      smooth neck mass with enough poly budget to avoid the decimated square prism. Do not hide it
-      with a torus/flat disk collar; both read as a brace or shelf.
+- [x] Fix the neck junction without touching the accepted face: cut the decimated neck column
+      radially (all-vertex test inside r=0.085) so the shirt shoulder silhouette stays intact,
+      then bridge the opening with a wide 20-segment skin cone from r=0.10 to r=0.056. The lower
+      cone is painted cloth so the opening reads as a V-neck rather than bare chest. No torus,
+      disk shelf, neck brace or sawtooth collar.
+- [x] Seat the ankles in the shoes: remove the lower-leg x-narrowing, raise the shoe shell to
+      0.14 m and add a 0.10 m pant cuff at z=0.13 so the open tapered ankle is hidden.
+- [ ] Owner reviews the updated MPFB body renders (`tmp/npc-parts/mpfb_proto/renders60/`).
+      Remaining known defects: block-shaped shoe silhouette, white shirt hem forms a V at the
+      crotch, shirt still reads skin-tight, and the 2k-tri body budget leaves some angular thigh
+      facets. These are polish, not blockers for the body direction.
 - [ ] Fix the low-budget seams before any rollout: weld the torso/hip/arm components after the
-      bisects, protect the hip/knee loops during decimation (or rebalance head/body triangles), and
-      rebuild the shoes/ankles so the leg does not taper to a point above a block.
+      bisects, protect the hip/knee loops during decimation (or rebalance head/body triangles).
 - [ ] Record the production integration decision: either bake the approved MPFB body to a committed
       source GLB (CI and fresh checkouts stay MPFB-free) or keep the procedural body as the shipped
       path. Do not add the MPFB extension as a build/CI dependency.