Use godot physics instead of bullet to improve performance

source/arviz_godot/project/project.godot

@@ -154,6 +154,8 @@ avi_camera_playful={
 [physics]
 
 common/enable_pause_aware_picking=true
+3d/physics_engine="GodotPhysics"
+3d/active_soft_world=false
 
 [rendering]
 

source/arviz_godot/project/root.tscn

-[gd_scene load_steps=70 format=2]
+[gd_scene load_steps=71 format=2]
 
 [ext_resource path="res://bin/app/main.gdns" type="Script" id=1]
 [ext_resource path="res://bin/gui/user_interface.gdns" type="Script" id=2]