CLI integration with doxygen-rs?

Doxygen seems to be commonly used in C/C++ projects, and its annotations look pretty messy in Rustdoc.

bindgen chose to offload processing of Doxygen annotations to doxygen-rs. The problem is that the process_comment callback used as an integration point exists only in the bindgen's Rust API.

In my crates, I generally avoid using bindgen at build time, and have workflows based around running bindgen-cli instead. Having to replace shell one-liners with Rust programs is inconvenient.

Could bindgen-cli have some way of supporting doxygen annotations?

Add doxygen-rs as an optional Cargo feature? Or if you want bindgen to remain completely agnostic, maybe support filtering of comments by through stdin/stdout of a command? (so that doxygen-rs could provide an executable for this)

Start by tracing the bindgen-cli integration and the existing process_comment Rust API mentioned in the issue. Compare the optional doxygen-rs feature and stdin/stdout filtering approaches; done means an agreed CLI path supports Doxygen annotations without requiring a Rust build script.