feat: Restrict types for Spring and Tween

[webJose]

Closes Improve Spring data typing, or improving it so it doesn't bother about unsupported data types #14851

This PR introduces the MotionPrimitive and MotionRecord data types to accurately reflect what the algorithms of the Spring and Tween classes can handle.

The alternative would be to remove the throwing whenever an unsupported data type is found, but I suppose that is a breaking change and if that's the preferred route, then it would have to wait for Svelte v6. Therfore, this PR should greatly increase the accuracy of Intellisense when using Spring and Tween.

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Playground

pnpm add https://pkg.pr.new/svelte@14862

[webJose]

PR in draft mode. Kindly let me know if this is something the core team would like to pursue. If so, I'll follow any additional instructions I am given and take the PR out of draft mode. Thanks!

[Ocean-OS]

One thing to account for is that arrays containing numbers are supported, so perhaps MotionRecord could be changed to include arrays like so:

export type MotionRecord = {
	[x: string | number]: MotionPrimitive | MotionRecord | (MotionPrimitive | MotionRecord)[];
} | (MotionPrimitive | MotionRecord)[]

[webJose]

One thing to account for is that arrays containing numbers are supported, so perhaps MotionRecord could be changed to include arrays like so:

export type MotionRecord = {
	[x: string | number]: MotionPrimitive | MotionRecord | (MotionPrimitive | MotionRecord)[];
} | (MotionPrimitive | MotionRecord)[]

It's already accounted for. T extends from MotionRecord[string], which is MotionPrimitive, MotionRecord or arrays containing either of those. You can test this in the TS playground.