### Godot version

v4.1.rc1.mono.official [1f9e540f1]

### System information

Godot v4.1.rc1.mono - Windows 10.0.19045 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1660 Ti with Max-Q Design (NVIDIA; 31.0.15.3179) - Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz (12 Threads)

### Issue description

When NavigationAgent3D is instantiated at runtime and added to the scene tree, invisible/impassable obstacle is added at the global origin position (0, 0, 0).

### Steps to reproduce

1. Run attached MRP
2. Click with `left mouse button` at the world origin to make agent walk
3. Click `space` on your keyboard to instantiate NavigationAgent3D
4. Click left mouse button to walk through world origin position again
5. Player gets stuck on obstacle at the world origin position

https://github.com/godotengine/godot/assets/8630984/fc9b32fb-25cb-46d6-9a98-ff299e2c0b1c



### Minimal reproduction project

[MRP.zip](https://github.com/godotengine/godot/files/11910363/MRP.zip)

return debug_path_custom_color;
}
void NavigationAgent3D::set_debug_path_custom_point_size(float p_point_size) {
#ifdef DEBUG_ENABLED
	if (Math::is_equal_approx(debug_path_custom_point_size, p_point_size)) {
		return;
	}
	debug_path_custom_point_size = MAX(0.0, p_point_size);
	debug_path_dirty = true;
#endif 
}
float NavigationAgent3D::get_debug_path_custom_point_size() const {
	return debug_path_custom_point_size;
}
#ifdef DEBUG_ENABLED
void NavigationAgent3D::_navigation_debug_changed() {
	debug_path_dirty = true;
}
void NavigationAgent3D::_update_debug_path() {
	if (!debug_path_dirty) {
		return;
	}
	debug_path_dirty = false;
	if (!debug_path_instance.is_valid()) {
		debug_path_instance = RenderingServer::get_singleton()->instance_create();
	}