//! Process-environment helpers used by the cursus binary.
//!
//! The library boundary never reads environment variables directly (ADR-030);
//! these helpers live in the binary and feed the relevant values into
//! [`cursus::Env`] / forge-client constructors.
/// Returns the first non-empty value from the given environment variables,
/// or `None` if none are set or all are empty.
pub
/// Resolves the BCP 47 locale tag for user-visible messages.
///
/// Priority order:
/// 1. `CURSUS_LOCALE` environment variable (explicit override)
/// 2. System locale via `sys_locale::get_locale()` (cross-platform)
/// 3. `"en"` fallback
pub