Add a spring-simulated variant

[timcreatedit]

I would love to have a variant of the widget that is animated using spring simulations instead of curves.

This would allow the animations to redirect very smoothly when the position changes during the animation.

I could give this a shot, but I would solve it by adding a dependency to (my own) springsterpackage. Would you be interested in that?

https://pub.dev/packages/springster

[chooyan-eng]

@timcreatedit Thank you for your suggestion! And yeah, adding spring simulations has been one of the biggest challenges for this package, which @lukepighetti also suggested on X here.

To be honest, I have no knowledge about physics, so let me start by checking your springster package first.

[chooyan-eng]

@timcreatedit I've briefly checked your springster package. It seems SpringSimulationController and SpringSimulationController2D make Flutter's SpringSimulation easily available, and they will equip animated_to with a spring-simulated version of AnimatedTo, maybe AnimatedTo.spring() like below.

/// this internally creates spring-simulated version of `RenderAnimatedTo` 
/// which uses `SpringSimulationController` or `SpringSimulationController2D` depending on the given [spring].
AnimatedTo.spring(
  globalKey: _key,
  spring: SimpleSpring.bouncy,
  child: AnyWidget(),
),

I'm still not sure my idea works well, so I'll try to implement this later.

[timcreatedit]

I would also gladly contribute this, if you want me to