Kiki Agent 动画
客户端实现方案

final class KikiTypingView: UIView {
    private let base = UIImageView(image: UIImage(named: "kiki_typing_base"))
    private let hands = UIImageView(image: UIImage(named: "kiki_typing_hands"))

    override init(frame: CGRect) {
        super.init(frame: frame)
        [base, hands].forEach {
            $0.contentMode = .scaleAspectFit
            $0.translatesAutoresizingMaskIntoConstraints = false
            addSubview($0)
            NSLayoutConstraint.activate([
                $0.leadingAnchor.constraint(equalTo: leadingAnchor),
                $0.trailingAnchor.constraint(equalTo: trailingAnchor),
                $0.topAnchor.constraint(equalTo: topAnchor),
                $0.bottomAnchor.constraint(equalTo: bottomAnchor)
            ])
        }
    }

    required init?(coder: NSCoder) { fatalError("init(coder:) not implemented") }

    func setTyping(_ typing: Bool) {
        hands.layer.removeAnimation(forKey: "kiki.typing")
        guard typing, !UIAccessibility.isReduceMotionEnabled else { return }

        let animation = CAKeyframeAnimation(keyPath: "transform.translation.y")
        animation.values = [0, 0.9, -0.3, 0.6, 0]
        animation.keyTimes = [0, 0.25, 0.5, 0.75, 1]
        animation.duration = 0.65
        animation.timingFunction = CAMediaTimingFunction(name: .easeInEaseOut)
        animation.repeatCount = .infinity
        animation.isRemovedOnCompletion = false
        hands.layer.add(animation, forKey: "kiki.typing")
    }
}

@Composable
fun KikiTyping(
    isTyping: Boolean,
    modifier: Modifier = Modifier
) {
    val transition = rememberInfiniteTransition(label = "kikiTyping")
    val offsetY by transition.animateFloat(
        initialValue = 0f,
        targetValue = 0f,
        animationSpec = infiniteRepeatable(
            animation = keyframes {
                durationMillis = 650
                0f at 0 using FastOutSlowInEasing
                0.9f at 162
                -0.3f at 325
                0.6f at 487
                0f at 650
            }
        ), label = "handsOffset"
    )

    Box(modifier) {
        Image(painterResource(R.drawable.kiki_typing_base), null,
            modifier = Modifier.matchParentSize(), contentScale = ContentScale.Fit)
        Image(painterResource(R.drawable.kiki_typing_hands), null,
            modifier = Modifier.matchParentSize().graphicsLayer {
                // Compose follows the system animator duration scale.
                translationY = if (isTyping) offsetY * density else 0f
            }, contentScale = ContentScale.Fit)
    }
}