pub fn discover_droid_binary(configured: Option<&str>) -> Result<PathBuf>Expand description
Locate a working droid binary.
Order: configured → KRANZ_DROID_BIN env var → droid on PATH →
well-known install locations. Each candidate is validated by running it
with --version; the first one that succeeds wins. Errors list every
attempt so the user can see what was tried.
KRANZ_DROID_BIN, when set and non-empty, is an exclusive override:
only that path is probed, and a failure is returned immediately rather
than falling through to PATH or the well-known fallback locations. Naming
the binary explicitly and having it not work is an error, not a reason to
search elsewhere.