feat(smartfeed): Implement Smartfeed core: add feed validation, parsing, exporting and comprehensive tests

ts/index.ts

@@ -1,2 +1,16 @@
-export * from './smartfeed.classes.smartfeed.js';
-export * from './smartfeed.classes.feed.js';
+// Export classes
+export * from './classes.smartfeed.js';
+export * from './classes.feed.js';
+export * from './classes.podcast.js';
+
+// Ensure interfaces are explicitly exported
+export type { IFeedOptions, IFeedItem } from './classes.feed.js';
+export type {
+  IPodcastFeedOptions,
+  IPodcastItem,
+  IPodcastOwner,
+  IPodcastPerson,
+  IPodcastChapter,
+  IPodcastTranscript,
+  IPodcastFunding,
+} from './classes.podcast.js';