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.test.ts

@@ -0,0 +1,40 @@
+import { splitByUrl } from "./Util";
+
+describe("splitByUrl", () => {
+  it("should split a string by URLs", () => {
+    const inputStr =
+      "@npub1q6mcr8t not https://example.com- sure what your stack is, https://example.com but I made a https://example.com! simple example (https://example.com) of how https://example.com/yo-yo https://example.example.com to do this https://example.com, https://example.com?q=asdf for Next.js apps hosted on Vercel https://example.com. Scarcity in money provides the incentive to create abundance in other things as there is a mechanism to reliably store value. https://i.imgur.com/rkqhjeq.png Every form of money that could be inflated by way of force or technological advancement has been.";
+    const expectedOutput = [
+      "@npub1q6mcr8t not ",
+      "https://example.com-",
+      " sure what your stack is, ",
+      "https://example.com",
+      " but I made a ",
+      "https://example.com",
+      "! simple example (",
+      "https://example.com",
+      ") of how ",
+      "https://example.com/yo-yo",
+      " ",
+      "https://example.example.com",
+      " to do this ",
+      "https://example.com",
+      ", ",
+      "https://example.com?q=asdf",
+      " for Next.js apps hosted on Vercel ",
+      "https://example.com",
+      ". Scarcity in money provides the incentive to create abundance in other things as there is a mechanism to reliably store value. ",
+      "https://i.imgur.com/rkqhjeq.png",
+      " Every form of money that could be inflated by way of force or technological advancement has been.",
+    ];
+
+    expect(splitByUrl(inputStr)).toEqual(expectedOutput);
+  });
+
+  it("should return an array with a single string if no URLs are found", () => {
+    const inputStr = "This is a regular string with no URLs";
+    const expectedOutput = ["This is a regular string with no URLs"];
+
+    expect(splitByUrl(inputStr)).toEqual(expectedOutput);
+  });
+});