Function effective_exit_codes 

pub fn effective_exit_codes(
    spec: &Spec,
    path: &[SpecCommand],
) -> Vec<SpecExitCode>

The exit codes in effect for a command, CLI-wide declarations folded in.

Nearest wins per code, and the root’s order is preserved so a table reads the same way on every page. A command’s own codes append in declaration order.

Folded on read rather than at parse time, following unknown_flags: folding early would write the root’s codes into every command block on re-emission.