//! Process exit codes.
//!
//! Codes are part of the public contract: scripts and agents branch on them.
//! Note what is deliberately *not* encoded here — "the result set was truncated"
//! and "the result set was empty" are both success. Pagination state travels in
//! the output text (see `docs/adr/0003-output-ladder.md`), never in the exit code.
/// Exit code returned to the OS.