Reducing Cargo target directory size with -Zno-embed-metadata

Disk usage of the target directory is a commonly cited annoyance with Rust (and Cargo) – in the last year’s Annual Survey, it was the third most pressing issue of Rust users, right after slow compilation1 and subpar debugging experience. Given the “build everything from source” compilation model of Rust, and both debuginfo and incremental compilation being enabled by default in the dev Cargo…