Godot XR Tools 4.6.0-dev1

New dev release of XR Tools that fixes a number of issues introduced in Godot 4.7 and has a big refactor/cleanup applied to the code base.

A cleanup of this size does have a potential for introducing issues so we normally don't risk it, however as much of the code in XR Tools dates back to Godot 3.x days, we felt it was worth doing. Many thanks to @mubinulhaque for the extensive work done here.

We will likely have one more dev built with a few more fixes and dealing with any regressions from the refactor/cleanup before we have an official 4.6 release.