Function runtime_error_exit_code 

pub fn runtime_error_exit_code(error: &RuntimeError) -> i32

Map a runtime startup/serve error to its process exit code.

Listener and admin bind failures are EXIT_BIND_FAILURE; all other runtime errors are EXIT_RUNTIME_FAILURE. Shared by native startup and the compatibility execution facade so every entry point reports bind failures with the documented code instead of a generic runtime failure.