add rustfmt raw identifer sorting doc

Author: calebcartwright

src/rust-2024/rustfmt-raw-identifiers.md

@@ -0,0 +1,52 @@
+# Rustfmt: raw identifier sorting
+
+🚧 The 2024 Edition has not yet been released and hence this section is still "under construction".
+
+More information may be found in <https://github.com/rust-lang/rust/issues/124764>.
+
+## Summary
+
+`rustfmt` now properly sorts [raw identifiers].
+
+[raw identifiers]: https://doc.rust-lang.org/rust-by-example/compatibility/raw_identifiers.html
+
+## Details
+
+The [Rust Style Guide] includes [rules for sorting][sorting] that `rustfmt` applies in various contexts, such as on imports.
+
+Prior to the 2024 Edition, when sorting rustfmt would use the leading `r#` token instead of the ident which led to specious results.
+
+For example:
+
+```rust
+use websocket::client::ClientBuilder;
+use websocket::r#async::futures::Stream;
+use websocket::result::WebSocketError;
+```
+
+Which is now corrected in the 2024 Edition:
+
+```rust
+use websocket::r#async::futures::Stream;
+use websocket::client::ClientBuilder;
+use websocket::result::WebSocketError;
+```
+
+[Rust Style Guide]: https://doc.rust-lang.org/nightly/style-guide/index.html
+[sorting]: https://doc.rust-lang.org/stable/style-guide/index.html?highlight=sort#sorting
+
+## Migration
+
+The change can be applied automatically by running `cargo fmt` or `rustfmt` with the 2024 Edition.
+
+With a Cargo.toml file that has `edition` set to `2024`:
+
+```sh
+cargo fmt
+```
+
+Or by running `rustfmt` directly:
+
+```sh
+rustfmt foo.rs --style-edition 2024
+```