Markets traded cautiously ahead of Fed Chair Kevin Warsh’s pivotal Jackson Hole speech tomorrow, with the S&P 500 rising 0.24% and the Nasdaq gaining 0.56% as NVIDIA’s post-earnings rally continued. Oil rebounded 3.7% to $88.45/barrel after plunging 5% on Iran-Oman Hormuz talks, while gold stabilized near $4,640/oz and Bitcoin held above $78,500. European markets were…