SwiftGodot 0.46 - performance, correctness and Godot 4.3 support

[migueldeicaza]

SwiftGogot 0.46 is out.

Special thanks go to Elijah on his tireless work to track down various forms
of memory leaks, ownership counts and various crashes caused by incorrect
ownership rules.

Release details:

Features

• Support for Godot 4.3 APIs, apologies for the delay.

Performance

• Allocation-less marshaling for built-in and class types methods.
  The runtime no longer needs to allocate temporary variables to call
  into Godot, we now pass data directly from the stack (Elijah
  Semyonov)

• More progress to perform Vector3 operations in Swift-land, without
  having to call into Godot to do the (Elijah Semyonov)

• Arguments are now borrowed, without being copied (Elijah Semyonov)

Quality of Life Improvements

• Warn users if they declare types that conflict with Godot types (Rob
  Mayoff)

• Large class of memory leaks with variants have been fixed in a
  multi-week effort by Elijah Semyonov that tracked every single
  dangling reference to their root cause. This is truly a gift of the
  gods for all SwiftGodot users.

  Fix a 544 leak #545, String leak when wrapping in a Variant #541, Fix a 541 leak #542, Revisit indexing operators and fix leaks and crashes #548, Hardcoded constructors marshaling fix, some leaks fixes #550, Object.call leaks #552, GD.str leaks #551

  And also a great test suite to ensure we do not regress.

• New marshalling infrastructure that works on Windows, and removes
  the previous optimization that was failing to compile on Windows.

Fundamentals

• Fix deprecated code usage (Luke Puchner-Hardman, Elijah Semyonov)

• Fix a scenario where we did not lookup the most-derived type (Justin
  Anderson)

• Fix crashes on some indexer operation (Elijah Semyonov)

Maintenance

• Avoid name clashes with swift language keywords (Jakob
  Winkler)

• Remove hard-coded values on my development system so everyone can
  enjoy it (Elijah Semyonov)