//! Shared helpers for the external-validation tests.
/// True when `bin` is installed and on the PATH. Used by the ignored
/// validation tests to skip gracefully instead of failing when the
/// external tool is absent.
///
/// Presence is detected by spawning `bin --help` (a flag every target
/// tool accepts) and checking only that the process ran: a spawn error
/// means the binary is absent, while any exit status means it is there.
pub