Raise character limits and document optional Blender MCP

docs/npc-model-sourcing.md

@@ -28,7 +28,7 @@ Any expansion must preserve the existing integration contract:
   `Hips`, `Spine`, `Neck` at the contract rest positions;
 - five tint slots (`skin`, `cloth`, `pants`, `accessory`, `hair`);
 - front on Blender −Y / Godot +Z, feet near the floor, 1.6–2.1 m height;
-- at most 8,000 triangles and 8,000 glTF vertices per character;
+- at most 16,000 triangles and 16,000 glTF vertices per character;
 - gear attach points at head, back, chest and hand.
 
 The existing `audit` command is the gate. A source that looks good in a preview
@@ -68,8 +68,8 @@ Every example fails the unmodified `audit` contract:
 | `npc_base` mesh node | no | no | no | no | no |
 | Required 13 bones | no (62 different names) | no rig | no (19 different names) | no (19 different names) | no rig |
 | Five tint slots | no | no | no | no | no |
-| ≤ 8,000 tris | yes | yes | yes | yes | no |
-| ≤ 8,000 verts | no (10.5–13k) | yes | yes | yes | no (19k) |
+| ≤ 16,000 tris | yes | yes | yes | yes | yes |
+| ≤ 16,000 verts | yes (10.5–13k) | yes | yes | yes | no (19k) |
 | Feet on floor | yes | yes (2.7 m scale) | yes (−11 mm) | yes | no (needs scaling) |
 | Height 1.6–2.1 m | yes | no (2.7 m) | no (1.45 m) | no (1.48 m) | needs scale |
 | Skinned / UV mapped | yes / yes | no / yes | yes / yes | yes / no | no / no |
@@ -211,7 +211,7 @@ the A-pose arms down (−38°/+38°) and scales them **1.63×** to the contract
 arm, welds the split vertices, smooth-shades, adds the 13-bone contract armature
 with the project's distance-to-bone `_auto_weights`, paints the five slot regions,
 renames the mesh to `npc_base`, and exports `makehuman_retargeted.glb` — **6,444 /
-8,000 tris, 7,726 / 8,000 verts**, 14 bones, skinned, arm-down, grounded, five
+16,000 tris, 7,726 / 16,000 verts**, 14 bones, skinned, arm-down, grounded, five
 slots, no contract issues. The proportion warp (1.63× arms) is the same class of
 issue that blocked Quaternius; here it is accepted, but the vision review shows
 it distorts the deltoid/shoulder, the decimated hands are blocky, and the slot
@@ -283,7 +283,7 @@ are:
 - Weld duplicate seam vertices before decimating. Quaternius' 12k imported
   vertices are mostly UV/normal splits; the underlying surface is much smaller,
   but the glTF budget counts the splits after export.
-- Decimate to a target below 8,000 tris/verts, then re-unwrap only if the
+- Decimate to a target below 16,000 tris/verts, then re-unwrap only if the
   existing UVs cannot survive the material remap. The current library uses
   smart projection at 80° to keep islands large.
 - Map materials by semantic role, not by source name. A source "Purple" or