Record the tmp/npc-parts working-set layout decision

TODO.md

@@ -49,9 +49,11 @@ the rest of §C remains the broad review checklist.
       prototype detail unless a separate contract decision approves it.
       Recorded in `docs/3d-model-review.md` §Baseline inventory and
       `docs/blender-assets.md` §Frozen fallback boundary.
-- [ ] Choose a local working-set layout: `tmp/npc-parts/<variant>/` (gitignored) for part `.blend`
+- [x] Choose a local working-set layout: `tmp/npc-parts/<variant>/` (gitignored) for part `.blend`
       and preview GLBs; only the assembled character GLBs, AO/maps, manifest and review sheets are
       committed. Do not add a new committed `.blend` source tree without a docs/ADR decision.
+      Recorded in `docs/3d-model-review.md` §Working-set layout and
+      `docs/asset-tooling.md` §Recommended part-workflow.
 
 ### 2. Local part pipeline
 

docs/3d-model-review.md

@@ -201,6 +201,13 @@ capture). Pass conditions:
 tests, the 48-frame baseline and the 96-frame pose/context review all stay authoritative; the new
 face/hands captures are the visual bar for this track.
 
+### Working-set layout
+
+Part sources and preview GLBs live under `tmp/npc-parts/<variant>/` (gitignored by the root
+`tmp/` rule); only the assembled character GLBs, AO/maps, the manifest and the review sheets are
+committed. No new committed `.blend` source tree is added without a docs/ADR decision — the
+frozen `npc_base.blend` stays the only tracked `.blend`.
+
 ## Scorecard skeleton
 
 Verdicts use `qa-review` semantics: **P0** (blocker: wrong scale, broken normals, budget fail),