On the fog-choked night of October 17, 2019, San Francisco was unusually quiet. The skyline shimmered faintly under a moon obscured by mist, and the Golden Gate Bridge stretched like a sleeping serpent across the dark bay. In the Marina District, 28-year-old Lina Moreno was returning from her late-night shift at a biotech firm. She walked her usual route, earbuds in, unaware her life was about to change forever.As she passed Fort Mason Park, her phone crackled. The music distorted into static, and the streetlights flickered. Then, a high-pitched hum vibrated through the ground. Startled, Lina yanked her earbuds out