feat(PublicIp): Add PublicIp service and refactor SmartNetwork to use it; remove public-ip dependency; update exports, docs and dependencies

ts/index.ts

@@ -1,4 +1,5 @@
 export * from './smartnetwork.classes.smartnetwork.js';
 export type { SmartNetworkOptions, Hop } from './smartnetwork.classes.smartnetwork.js';
+export { PublicIp } from './smartnetwork.classes.publicip.js';
 export { setLogger, getLogger } from './logging.js';
 export { NetworkError, TimeoutError } from './errors.js';