Function basename_exe 

pub fn basename_exe(cmdline: &str) -> String

Strip the executable’s directory from a cmdline headline so the row reads cargo nextest run, not /opt/homebrew/bin/cargo nextest run. Only the FIRST token (the executable) is basenamed; args are kept verbatim (they carry the distinguishing detail). A first token with no / (e.g. a postgres: walwriter process title) is unchanged.