fix: fixed problem with brand

Author: tegefaulkes

.npmrc

@@ -6,7 +6,6 @@ import type { IPv4, IPv4Mask, IPv6, IPv6Mask } from 'ip-num';
  */
 type Opaque<K extends string, T> = T & { readonly [brand]: K };
 declare const brand: unique symbol;
-export { brand };
 
 /**
  * Generic callback