[bug]: Shorthands don't merge with transform values

Which react-spring target are you using?

• @react-spring/web
• @react-spring/three
• @react-spring/native
• @react-spring/konva
• @react-spring/zdog

What version of react-spring are you using?

9.4.5

What's Wrong?

(You probably know this one already, so please ignore if it is on a to-do list already.)

If I want to go from one transform value to another, with the library, I can't use shorthands in the to value, if I am starting off with a from value (which cannot have shorthands).

So the only way you can really go if you have a from transform string is to another transform string.

Is this by design? Not sure this is a bug. But since I spent a bunch of time learning this lesson, thought I'd share it.

To Reproduce

import { useSpring } from 'react-spring'

const [props, api] = useSpring(() => {
  from: { transform: 'scale3d(0.1, 0.1, 0.1) translate3d(0, -1000px, 0)' }
  to: { scale3d: '0.475 0.475 0.475' }
})

return <animated.div style={{props}} />

Expected Behaviour

For the shorthands to merge with the initial transform value in coming up with a final value.

Link to repo

Reproduce the example with @react-spring/web and useSpring, starting with a from transform string and a to shorthand. Trace how transform values and shorthands are parsed and combined. Done means the shorthand is merged with the initial transform value, with coverage for this reproduction.