Function compile_options_split 

pub fn compile_options_split(
    project_root: impl Into<PathBuf>,
    paths: ProjectPaths,
) -> CompileOptions

CompileOptions::split(project_root, paths), with every source pre-read. Discovers exactly the files CompileOptions::split itself would compile — built from the same paths this call also hands to split, not re-derived from bynk.toml through a second read, so the two can never disagree.