[feat]: Move to keyframe

A clear and concise description of what the feature is

import { Component, createRef } from 'react'
import { Controller, animated } from '@react-spring/web'

class AnimatedComponent extends Component {
  isShowing = createRef(false)
  animations = new Controller({ opacity: 0 })


  render() {
    return (
      <>
        <animated.div style={this.animations.springs}>I will fade</animated.div>
      </>
    )
  }
}

if i want div to animate to 50% of the whole animation
i could just call some function like animation.moveTo(0.5) or animation.moveTo('50%')

Why should this feature be included?

A lot of animations will become handy

Please provide an example for how this would work

No response

Start by reading the Controller and animated usage shown in the issue, then inspect the existing animation API and related tests in the repository. Clarify the intended moveTo behavior, supported position format, and completion criteria before identifying the implementation and test locations.