[$] Some recent and notable changes to Rust

The Rust project makes incremental releases every six
weeks, a fact that makes it easy to overlook some of the
interesting changes coming to the language, such as new
ABIs, better debugger support, asynchronous traits, and
support for C strings.
The end of the year provides an opportunity to look back
over the past several months of updates, and to look
forward to what to expect in 2024.