This code replicated iOS 18 lock screen clock text change animation.

NumericTransion.swift

extension View {
    @ViewBuilder
    func numericTransition(_ value: Double) -> some View {
        if #available(iOS 17.0, *) {
            contentTransition(.numericText(value: value))
                .animation(.easeInOut(duration: 0.3), value: value)
        } else {
            transition(.opacity)
                .animation(.easeInOut(duration: 0.2), value: value)
        }
    }
}