feat: Examples / Implementations for key request

[cre8]

Section 3.5 lists 3 options to receive the key of an issuer:

• JWT VC Issuer Metadata
• X.509 Certificates
• DID Document resolution

Right now the library defines "bring your own crypto". Meaning the the user has to implement the getVerifier(publicKeyJWK: object): Promise<(data: string, signatureBase64url: string) => Promise<boolean>>; by himself. The data field includes the encoded header and payload field, therefore all three options can be implemented.

@lukasjhan do you think it makes sense? We can not implement to resolve all did elements, but we could give some examples for this.

[lukasjhan]

Yeah we could give them examples or implementations.

We already provide implementation for crypto. An example is the ES256 algorithm available in nodejs and broswer. And also we plan to support React Native env.

I think it's better to provide simple implemenation in our package.

[lukasjhan]

I think we can make them by platform(nodejs, web etc.) or we can make pass the signer or verifier as a param.
Which way do you prefer? @cre8

[cre8]

maybe it's enough to mention it in a readme, since the demanded implementation can be different: some are fine with the universal resolver, others want to resolve it locally. So we tell them how to implement it to give some hints.

[lukasjhan]

maybe it's enough to mention it in a readme, since the demanded implementation can be different: some are fine with the universal resolver, others want to resolve it locally. So we tell them how to implement it to give some hints.

Okay I'll write a brief explanation on docs. Then Let's talk about more with the PR