What is the .sql file doing? Why are you wanting to execute SQL from a file in a (shared) file path? Is it so that it can be dynamic? Is...

This what you're looking for?

DECLARE @XML xml;
SET @XML =
'<tokens>
<token>
<typeid>1</typeid>
<p1>0.15</p1>
</token>
<token>
<typeid>1</typeid>

No, types are database bound, and can only be referenced within that database. For example, on my environment:
USE Sandbox;
GO
--This fails
DECLARE @test-2 Assets.app.OrderItems;
GO

USE Assets;