Function nova_rt_fs_exists 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn nova_rt_fs_exists(path: *const NovaStr) -> i8

Whether path exists. Cannot distinguish absent from unreadable, because nova-spec/20-STDLIB.md §5 gives exists a Bool return rather than a Result; that is the spec’s choice and is left alone.

Safety

path must point to a live NovaStr.