Announcing `async fn` and return-position `impl Trait` in traits

The Rust Async Working Group announces the progress of enabling 'async fn' in traits. Rust 1.75 includes support for '-> impl Trait' notation and 'async fn' in traits. The use of '-> impl Trait' and 'async fn' in public traits is discouraged due to limitations and the inability to put additional bounds on the return type. The post also discusses the use of 'trait_variant::make' proc macro for multithreaded runtimes and the plan to enable dynamic dispatch in the future.