Guard gear fit with headless and Blender regression checks

The Python fit test now caps the glasses at 0.70x head width and requires a
positive bag clearance on both the coat and dress. The Godot character suite
loads head/back gear on six roles and checks attach parents, head width and
brow bounds, and that back gear reaches beyond the 0.26 m body silhouette.
Rebuilt and re-baked all 18 gear assets; no-op GLB export churn was reverted.
Headless 229/229, Python 87/87.

MEMORY.md

@@ -241,6 +241,11 @@ Session memory for durable decisions, state, and gotchas. Keep concise, remove o
   same colliders/obstacles, and collects library emissives for `set_night_mode()`.
   `LIBRARY_TRIANGLE_BUDGET` = 60k (current ~27,986). Library props are excluded from
   `PROP_PLACEMENTS` only when they need dedicated slots (door/marquee/sedan/handrail/lantern).
+  **Gear fit (v0.6.1):** `fit` measures head width (0.315 m), skirt/hip radius and gear bounds;
+  sunglasses are 0.202 m, the bag's body inner face is 0.262 m (coat 0.225, dress 0.260), and the
+  helmet is lifted 2 cm above the brow. `test_npc_character` guards head/back gear in Godot.
+  Blender's GLB export is byte-nondeterministic for unchanged assets (padding/index order), so do
+  not commit a full no-op rebuild; rebuild only the assets whose geometry changed.
 - **v0.6.0 environment pass:** `tools/bake_ao.py` bakes 256² AO maps per library asset
   (`<name>_ao.png`, red channel) and `Materials.apply_ao()`/`SurfaceMaterials` wire them in;
   `tools/make_normal_maps.py` derives tangent normals for the 1024² brick/concrete/asphalt

TODO.md

@@ -30,11 +30,14 @@ live in `tools/blender_assets.py` (`_build_gear()`), the contract in `docs/blend
       the hood leaves the face readable; the helmet brim sat on the brow, so the whole helmet was
       lifted 2 cm and rebuilt/re-baked. Beanie uses the same capped-shell sizing as the cap and is
       currently unused; it is covered by the upcoming headgear regression check.
-- [ ] Rebuild the gear (`build`) and re-bake AO (`tools/bake_ao.py`), then
+- [x] Rebuild the gear (`build --only <18 gear names>`) and re-bake AO (`tools/bake_ao.py --only
-      `godot --headless --path . --import`.
+      <same>`), then `godot --headless --path . --import` (clean). Blender's GLB export is
-- [ ] Add a regression test: `tools/test_blender_assets.py` checks the glasses width against the
+      byte-nondeterministic for unchanged assets (padding/index order changes), so the no-op churn
-      head width, and `src/test/tests/test_npc_character.gd` checks the head/back attach nodes
+      was reverted; only the intended sunglasses, bag, and helmet assets are committed.
-      stay outside the body silhouette radius.
+- [x] Add a regression test: `tools/test_blender_assets.py` limits the glasses to 0.70x head
+      width and requires positive bag clearance on both coat and dress;
+      `test_npc_character.test_head_and_back_gear_clear_the_body_silhouette` loads the gear on
+      six roles and checks head-parent/width/brow bounds plus back-parent/0.26 m outer radius.
 - [ ] Re-capture the portrait (`--stages=day,portrait`) and the gallery shots; record the
       before/after in `docs/screens/realism/<date>-gear/`.
 - [ ] Consider a second character close-up for a hoodie/winter NPC so headgear is covered too

docs/blender-assets.md

@@ -41,7 +41,7 @@ flatpak run org.blender.Blender --background \
   --python "$PWD/tools/blender_assets.py" -- render
 python3 tools/blender_assets.py sheet   # -> docs/blender_previews/sheet_<category>.jpg
 python3 tools/blender_assets.py audit   # stdlib only; exit 1 on any issue
-python3 tools/blender_assets.py fit     # head/clothing fit, per character
+python3 tools/blender_assets.py fit     # head/clothing fit + bag-body clearance, per character
 python3 tools/blender_assets.py list
 godot --headless --path . --import      # after any rebuild
 ```

src/test/tests/test_npc_character.gd

@@ -191,6 +191,68 @@ func test_library_gear_attaches_to_the_contract_points() -> bool:
 	responder.free()
 	return a and b and c and d
 
+## Horizontal bounds of a gear GLB in its attach-node space. The head/back
+## contract is measured against the Blender fit report (head width 0.315 m,
+## widest body silhouette 0.26 m); this catches a gear shrinking back inside
+## the body or a cap sinking below the brow.
+func _gear_bounds(node: Node3D) -> AABB:
+	var box := AABB()
+	var first := true
+	for child in node.find_children("*", "MeshInstance3D", true, false):
+		var mi := child as MeshInstance3D
+		var b: AABB = mi.get_aabb()
+		# Gear meshes have no extra transform below the attach node.
+		if first:
+			box = b
+			first = false
+		else:
+			box = box.merge(b)
+	return box
+
+func test_head_and_back_gear_clear_the_body_silhouette() -> bool:
+	const HEAD_WIDTH := 0.315
+	const WIDEST_BODY_RADIUS := 0.26
+	var problems: Array[String] = []
+	var seen := {}
+	for npc_type in [Rules.NpcType.TOURIST, Rules.NpcType.INFLUENCER,
+			Rules.NpcType.RESPONDER, Rules.NpcType.PERFORMER,
+			Rules.NpcType.DELIVERY, Rules.NpcType.TRESPASSER]:
+		var avatar := _avatar(npc_type, 5)
+		for child in avatar.find_children("Gear_*", "Node3D", true, false):
+			var gear := child as Node3D
+			var name := gear.name.trim_prefix("Gear_")
+			var attach := str(NpcAvatar.GEAR_ATTACH.get(name, ""))
+			if attach != "head" and attach != "back":
+				continue
+			seen[attach + ":" + name] = true
+			var box := _gear_bounds(gear)
+			if attach == "head":
+				var parent_name := gear.get_parent().name
+				if parent_name != "Head":
+					problems.append("%s is not under Head" % name)
+				if box.size.x > HEAD_WIDTH * 1.70:
+					problems.append("%s is %.3f m wide (head %.3f)" % [
+						name, box.size.x, HEAD_WIDTH])
+				# The hood wraps the neck; all other headgear must start on the skull.
+				if name != "hood" and box.position.y < 0.0:
+					problems.append("%s starts %.3f m below the head origin" % [
+						name, box.position.y])
+			else:
+				if gear.get_parent().name != "Rig":
+					problems.append("%s is not under Rig" % name)
+				var outer_x := maxf(absf(box.position.x), absf(box.end.x))
+				var outer_z := maxf(absf(box.position.z), absf(box.end.z))
+				if maxf(outer_x, outer_z) < WIDEST_BODY_RADIUS:
+					problems.append("%s only reaches %.3f m (body %.3f)" % [
+						name, maxf(outer_x, outer_z), WIDEST_BODY_RADIUS])
+		avatar.free()
+	for required in ["head:sunglasses", "head:firefighter_helmet", "head:cap",
+			"back:shoulder_bag", "back:backpack", "back:scba_tank"]:
+		if not seen.has(required):
+			problems.append("missing %s" % required)
+	return TestUtils.check(problems.is_empty(),
+		"head/back gear clears the body silhouette (%s)" % str(problems))
+
 func test_fixed_detail_materials_are_not_tinted() -> bool:
 	var avatar := _avatar(Rules.NpcType.RESPONDER, 3)
 	var mi := avatar.find_child("npc_base", true, false) as MeshInstance3D

tools/test_blender_assets.py

@@ -53,7 +53,8 @@ class BuiltAssetTests(unittest.TestCase):
         self.assertAlmostEqual(coat["reference"]["clothing_radius"], 0.225, places=3)
         sunglasses = next(row for row in coat["gear"] if row["name"] == "sunglasses")
         self.assertEqual(sunglasses["attach"], "head")
-        self.assertLess(sunglasses["width"], coat["reference"]["head_width"])
+        self.assertLessEqual(sunglasses["width"],
+                             0.70 * coat["reference"]["head_width"])
         bag = next(row for row in coat["gear"] if row["name"] == "shoulder_bag")
         self.assertEqual(bag["attach"], "back")
         self.assertGreaterEqual(bag["x_extent"], 0.2)
@@ -64,7 +65,10 @@ class BuiltAssetTests(unittest.TestCase):
                 self.assertEqual(len(row["min"]), 3)
                 self.assertEqual(len(row["max"]), 3)
         self.assertIn("npc_dress", report)
-        self.assertAlmostEqual(report["npc_dress"]["reference"]["clothing_radius"], 0.26, places=3)
+        dress = report["npc_dress"]
+        self.assertAlmostEqual(dress["reference"]["clothing_radius"], 0.26, places=3)
+        dress_bag = next(row for row in dress["gear"] if row["name"] == "shoulder_bag")
+        self.assertGreater(dress_bag["x_clearance"], 0)
 
     def test_manifest_covers_catalogue(self):
         manifest = json.loads(ba.MANIFEST.read_text(encoding="utf-8"))