Rust bindings for Godot 4 - Release v0.3.5

cross-posted from: https://vger.social/post/24108563

🌻 Highlights

• PhantomVar<T> for properties without a backing field
• Base::to_init_gd() to access pointer during initialization
• Gd::try_dynify() for runtime trait downcast
• Further improvements to match_class! dispatch

📚 Further reading

Full Changelog.