fix: remove @anonklub/proof package

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          I see you are still using the `ProofRequest` object in the ui.

@anonklub/proof was meant as a package to make server side proof.
As we now do client side proofs I don't see a need for that separate package anymore.

Shoudn;t we move ProofRequest either to the new spartan worker package or define it directly in the ui (ui/src/lib)

Moreover this should be a redefined ProofRequest class.
The original class has some methods to submit and getResult from the proving server... this we definitely don't need anymore.

Originally posted by @sripwoud in #295 (comment)

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#295 (comment)

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#295 (comment)