fix: improve unified settings (#3160)

packages/lib/client-only/cookies.ts

@@ -0,0 +1,17 @@
+/**
+ * Read a cookie value from `document.cookie`.
+ *
+ * Client-side counterpart of `extractCookieFromHeaders`. Only works for cookies that
+ * are not `HttpOnly`, such as the preferred team URL cookie.
+ */
+export const extractCookieFromDocument = (cookieName: string): string | null => {
+  const cookiePairs = document.cookie.split(';');
+
+  const cookie = cookiePairs.find((pair) => pair.trim().startsWith(`${cookieName}=`));
+
+  if (!cookie) {
+    return null;
+  }
+
+  return cookie.split('=')[1].trim();
+};