I need a clean, minimalistic animated highlight for the five-item bottom navigation bar in my iOS app (Routes, Activity, Navigate, Challenges, Profile). When a user taps a tab, a rounded rectangle should slide to the new position with a springy, slightly bouncy motion that feels fluid at 60 fps. The highlight will stay a single, neutral accent color; no per-tab color changes are required. Please implement this in Swift (UIKit or SwiftUI—whichever you prefer) and deliver: • fully-commented source code or a small demo project showing the component in action • integration notes so I can drop the view into my existing codebase without breaking Auto Layout or Safe Area constraints Acceptance criteria: the animation must start the moment a tab is pressed, complete smoothly without stutter, and the highlight must land precisely centered behind the selected icon and label on any current iPhone screen size.