Ts infer optional params from effect handler

[bloadvenro]

The problem with current createEffect typescript typings is that FN extends () => infer Done condition satisfies zero-or-one-arity effect handlers. Handler like (x?: TYPE) => any will produce Effect<void,...>. New test suite with updated snapshots displays these errors.

You may see new typings proposal partially improving current situation. I added some comments to explain why it was difficult to deal with type any.

The last commit contains finally updated snapshots to demonstrate how proposed typings work.

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[zerobias]

Wow, amazing! 😃 Big thanks!