Add verification key hash to the return type of ZkProgram compile

[rpanic]

Previously, ZkProgram and Smartcontract had different return types for compile(). This PR fixes this by adding in the hash to ZkProgram's function

[mitschabaude]

Fun fact: I have the same change in an open PR. So in this case I think it's fine to not add a changelog item, but if you still want to add it you can use the snippet in that PR: https://github.com/o1-labs/o1js/pull/1240/files#diff-06572a96a58dc510037d5efa622f9bec8519bc1beab13c9f251e97e657a9d4edR24

[rpanic]

Thanks @mitschabaude, did that. Also aligned the formatting, maybe merging will become easier

[dfstio]

Should the verify() argument also be changed from string to VerificationKey?

[mitschabaude]

Should the verify() argument also be changed from string to VerificationKey?

Great point. I'd like to see verify() handle both cases actually. String is the more logical input and VerificationKey is good for backwards compat

[mitschabaude]

I went ahead and pushed it to the upcoming release PR #1294