refactor: Turn the verifier crate into a library and rename it to surveyhero

[JayanAXHF]

Sub PR for #388

[Kobzol]

Could you please also update README.md, and anything else that mentions the old verifier name? Thanks!

[apiraino]

There seem to be a few unrelated stylistic changes I would have prefered to be in a separate commit (or in a small PR aside) but overall it seems that you just moved code around and "opened" some structs and functions so they are accessible from the binary. Is that correct?

Looks good to me (after changes suggested by Jakub), unless I missed anything. Jakub feel free to have a second look!

Thanks @JayanAXHF

[JayanAXHF]

Could you please also update README.md, and anything else that mentions the old verifier name? Thanks!

Done!

[JayanAXHF]

overall it seems that you just moved code around and "opened" some structs and functions so they are accessible from the binary. Is that correct?

Yes indeed!
I also fixed a few clippy lints :)

[Kobzol]

Thanks. I think that it is in general better if this is a library, we could use it for more interesting things in the future. One thing I'd love to see in general is having the export from a MD file to the SurveyHero text format, which could be imported into SH. That would really make live simpler for us when bootstrapping surveys (even if it won't be able to transfer all the details).