Ship the 0.9.0 production-quality milestone

Add mixer/accessibility settings, caption/reduce-motion hooks, audio volume
clamping, a 24-NPC performance smoke and shortened coat/dress stride for hem
clipping. Record the explicit Godot 4.3-CI/4.7-local matrix and the 0.9
production scope. Headless 250/250, Python 94/94, 24-NPC budget smoke passes.

src/game/npc_avatar.gd

@@ -1050,7 +1050,10 @@ func _animate(delta: float) -> void:
 		_idle_t = 0.0
 		_bob_phase += delta * (6.0 + speed * 1.7)
 		var urgency := 1.35 if reaction_mode == "flee" else 1.0
-		var stride := clampf(0.36 + speed * 0.10, 0.42, 0.7) * urgency
+		# Coats and skirts follow the hip/knee bones; a shorter stride keeps the
+		# hem from clipping through the legs during normal walking.
+		var hem_scale := 0.76 if character_model in ["npc_dress", "npc_coat"] else 1.0
+		var stride := clampf(0.36 + speed * 0.10, 0.42, 0.7) * urgency * hem_scale
 		_rig.position.y = sin(_bob_phase * 2.0) * 0.03
 		_rig.position.x = 0.0
 		_rig.rotation.x = sin(_bob_phase) * 0.03