feat(assets): face-based segmentation pipeline + solidify for hair/clothing

Segmentation:
- Face-based exclusive assignment (no overlap, no caps needed)
- Hips split from torso (pelvis as own segment)
- Torso_upper independent (spine_03 + clavicle, not a variant)
- Clavicle moved from arm_upper to torso_upper

Hair pipeline:
- Solidify modifier (20mm) for scalp hair volume
- Normal recalculation before solidify for consistent direction
- Eyebrows/facial hair NOT solidified
- Fixed mask generation (was outputting black, now white)

Clothing pipeline:
- Solidify modifier (25mm) for clothing thickness
- Peasant shoes added from Fantasy pack

Tooling:
- convert_outfit.py with solidify support
- inspect_glb.py, check_hair_symmetry.py for debugging
- Segment reference distribution locked
- Q-063 footsteps VFX filed

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

client/assets/characters/clothing/coveralls_basic/coverage.json

@@ -1,6 +1,7 @@
 {
   "hides": [
     "torso",
+    "hips",
     "arm_upper_l",
     "arm_upper_r",
     "arm_lower_l",

client/assets/characters/clothing/jacket_utility/coverage.json

@@ -1,6 +1,7 @@
 {
   "hides": [
     "torso",
+    "hips",
     "arm_upper_l",
     "arm_upper_r",
     "arm_lower_l",

client/assets/characters/clothing/pants_cargo/coverage.json

@@ -1,5 +1,6 @@
 {
   "hides": [
+    "hips",
     "leg_upper_l",
     "leg_upper_r",
     "leg_lower_l",

client/assets/characters/clothing/peasant_pants/coverage.json

@@ -0,0 +1,4 @@
+{
+  "hides": ["hips", "leg_upper_l", "leg_upper_r"],
+  "torso_variant": "full"
+}

client/assets/characters/clothing/peasant_shoes/coverage.json

@@ -0,0 +1,4 @@
+{
+  "hides": [],
+  "torso_variant": "full"
+}

client/assets/characters/clothing/peasant_tunic/coverage.json

@@ -0,0 +1,4 @@
+{
+  "hides": ["torso", "neck", "hips", "arm_upper_l", "arm_upper_r"],
+  "torso_variant": "full"
+}

client/assets/characters/clothing/shirt_henley/coverage.json

@@ -1,6 +1,7 @@
 {
   "hides": [
     "torso",
+    "hips",
     "arm_upper_l",
     "arm_upper_r"
   ],