Research NPC model sources and plan 0.11.0 expansion

docs/asset-tooling.md

@@ -129,6 +129,10 @@ with colliders/avoidance and drives their emissive parts from the day/night
 cycle. The single `npc_base.glb` and primitive props remain offline fallbacks.
 Contract and integration notes: [`blender-assets.md`](blender-assets.md).
 
+Sourcing and expansion research (no external model is shipped yet):
+[`npc-model-sourcing.md`](npc-model-sourcing.md) compares Quaternius, Kenney, Khronos and
+MakeHuman sources against the character contract and records the pending 0.11.0 decision.
+
 | Characters | Props |
 | --- | --- |
 | ![characters](../docs/blender_previews/sheet_npc.jpg) | ![props](../docs/blender_previews/sheet_props.jpg) |