Move axum-debug crate to workspace (#497)

* add axum-debug to workspace

* update readme

* add changes to changelog

* little docs update

* fix the gap

a tab has leaked into workspace Cargo.toml, it must be fixed

* address clippy warnings

axum-debug-macros/README.md

@@ -0,0 +1,23 @@
+[![License](https://img.shields.io/crates/l/axum-debug-macros)](https://choosealicense.com/licenses/mit/)
+[![Crates.io](https://img.shields.io/crates/v/axum-debug-macros)](https://crates.io/crates/axum-debug-macros)
+[![Docs - Stable](https://img.shields.io/crates/v/axum-debug-macros?color=blue&label=docs)](https://docs.rs/axum-debug-macros/)
+
+# axum-debug-macros
+
+Procedural macros for [`axum-debug`] crate.
+
+## Safety
+
+This crate uses `#![forbid(unsafe_code)]` to ensure everything is implemented
+in 100% safe Rust.
+
+## Performance
+
+This crate have no effect when using release profile. (eg. `cargo build
+--release`)
+
+## License
+
+This project is licensed under the [MIT license](LICENSE).
+
+[`axum-debug`]: https://crates.io/crates/axum-debug