fix URL parsing edge cases (#360)

This should fix the following:
- URLs in parentheses
- URLs at the end of a sentence

packages/app/src/Util.ts

@@ -222,3 +222,10 @@ export function tagFilterOfTextRepost(note: TaggedRawEvent, id?: u256): (tag: st
 export function groupByPubkey(acc: Record<HexKey, MetadataCache>, user: MetadataCache) {
   return { ...acc, [user.pubkey]: user };
 }
+
+export function splitByUrl(str: string) {
+  const urlRegex =
+    /((?:http|ftp|https):\/\/(?:[\w+?.\w+])+(?:[a-zA-Z0-9~!@#$%^&*()_\-=+\\/?.:;',]*)?(?:[-A-Za-z0-9+&@#/%=~_|]))/i;
+
+  return str.split(urlRegex);
+}