Document MPFB full-body NPC prototype status and seams

docs/npc-model-sourcing.md

@@ -54,6 +54,14 @@ the procedural head until the hair/body review and rollout in [`TODO.md`](../TOD
 The MakeHuman body should reuse the approved local head/hand parts rather than forking
 a second face implementation.
 
+The current local MPFB full-body prototype (`tmp/npc-research/build_mpfb_npc.py`) assembles the
+accepted head on an MPFB 2.0.18 body at **15,917 / 16,000 tris**, 1.811 m, 14 bones and 10
+materials, with project hands, rounded shoe shells, cuffs and flat slot colours. It is a review
+candidate, not a shipped asset: the neckline reads as a short collar, the 2k-tri body budget
+leaves boxy outer thighs, and torso/hip/arm seam gaps appear when the budget is raised. The
+production integration decision (bake a committed source GLB or keep the procedural body) and
+the owner review are tracked in `TODO.md`; MPFB itself must not become a CI/build dependency.
+
 ## Provenance rules
 
 - CC0 preferred; CC-BY only with attribution in `CREDITS.md`; no service asset