🎁 [Feature Request]: Separate macros into their own files

[ozgunozerk]

What is the feature you would like to see?

Right now, all the macros reside in lib.rs due to:

functions tagged with `#[proc_macro_attribute]` must currently reside in the root of the crate

However, by utilizing helper functions, we can eliminate the huge bodies, and make the lib.rs much shorter, and still place each macro to their own respective file for maintainability.