feat: add typescript types

[snyamathi]

Adds typescript types while trying to maintain as much flexibility as possible.

type Config = { foo: string };
const ycb = new Ycb<Config>(bundle);
const { foo } = ycb.read(context); // foo is a string

While the examples show the dimensions and main config at the top, neither of those is required.

In fact, the main config is technically not required. If you were to omit a main config, all you would get back is the delta, if any. I don't think this is how the library was intended to be used, and if you did want to omit the main config, you can give the generic type as a DeepPartial of your config, but this won't happen automatically.

type Config = DeepPartial<{ foo: string }>;
const ycb = new Ycb<<Config>>(bundle);
const { foo } = ycb.read(context); // foo is string | undefined

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