Update exports in index.ts to include .js extensions, add centralized WHOIS server fallbacks for TLDs in whois-fallbacks.ts, and integrate fallbacks into the ianaWhoisServerForTld function in whois.ts for improved error handling.

src/index.ts

@@ -1,2 +1,2 @@
-export * from "./lookup";
-export * from "./types";
+export * from "./lookup.js";
+// export * from "./types.js";