Fix login redirect — access result.data.token/user

Login/register pages now correctly unwrap API response {data: {token, user}}.
Cleaned up leftover apiFetch code.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/tasks/app/login/page.tsx

@@ -23,7 +23,7 @@ export default function LoginPage() {
     setError("");
     try {
       const result = await login({ email: email.trim() });
-      setAuth(result.token, result.user);
+      setAuth(result.data.token, result.data.user);
       router.push("/tasks");
     } catch (err) {
       setError(err instanceof Error ? err.message : "Chyba prihlaseni");