Execute one of 4 iOS audio tasks for FlowFlow (Rust/Dioxus 0.7), (1) enable background audio recording via background_modes + MixWithOthers, (2) handle AVAudioSession interruptions (phone calls/FaceTime) with auto-resume, (3) upgrade Dioxus 0.7 to 0.7.9, (4) implement Dynamic Island Live Activity for recording timer via ActivityKit. Use when user mentions "background audio", "AVAudioSession", "interruption handling", "Dynamic Island", "Live Activity", "Dioxus upgrade", "UIBackgroundModes", "cpal background", "Widget Extension", or asks to run a numbered prompt (1-4) from the background-audio plan.