ivanfernand2010-alt/fartlek-neo-bauhaus-ios ? reverse-engineered prompt

Build me a native iPhone app in Swift 6 and SwiftUI for guided fartlek and HIIT running workouts, with a bold Neo Bauhaus look, geometric, modular, and very clean. The app should let a runner start a session, follow timed interval prompts, and switch smoothly through the workout states with a simple, touch friendly interface. It should feel serious and safe, with clear audio cues, short Spanish voice prompts, and support for workout data like steps, heart rate, and basic telemetry if available.

I also want the app organized in a clean modular way, with separate pieces for workout logic, safety checks, audio, telemetry, persistence, layout, and UI. Make the screens easy to use on a phone while running, with big controls, a vertical layout, and a simple pause and tactical menu flow. If you need current Apple docs for anything recent, look them up online.