fix(utils): convert JWK with curv Ed25519 to X25519

[nickreynolds]

What is being changed

allow JsonWebKeys with crv = Ed25519 to be converted to crv = X25519

Quality

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• I want these changes to be integrated
• I successfully ran yarn, yarn build, yarn test, yarn test:browser locally.
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• I added unit tests.
• I added integration tests.
• I did not add automated tests because _________, and I am aware that a PR without tests will likely get rejected.

[codecov]

Codecov Report

Merging #1078 (9c5f2f5) into next (125bf42) will decrease coverage by 0.23%.
The diff coverage is 78.37%.

❗ Current head 9c5f2f5 differs from pull request most recent head 7c91ed3. Consider uploading reports for the commit 7c91ed3 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             next    #1078      +/-   ##
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- Coverage   80.25%   80.01%   -0.24%     
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  Files         118      127       +9     
  Lines        4056     4608     +552     
  Branches      875     1000     +125     
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+ Hits         3255     3687     +432     
- Misses        798      921     +123     
+ Partials        3        0       -3     

[mirceanis]

This looks great!
Do you plan to fill the todo test cases as well?

[nickreynolds]

I would like to add tests for all the unpack cases as well, but at least for JWK, I wouldn't know how to do that. We don't currently support importing JWKs into KeyManager, do we?

[mirceanis]

We don't currently support importing JWKs into KeyManager, do we?

No, we don't. Private key data has to be converted to hex. We should be able to do the conversion with existing utils/deps:
For JWK ec private keys this means converting the d property from base64 to base16.

[nklomp]

In our SSI Wallet we have code that actually has support to covert DID jwk and thus JWKs to hex. We intent to bring that to Veramo, but maybe you can already use it

https://github.com/Sphereon-Opensource/ssi-mobile-wallet/blob/79b7cb56a3d009f741463fb0ca0fb7997c1a090f/src/services/identityService.ts#L132

Called from https://github.com/Sphereon-Opensource/ssi-mobile-wallet/blob/79b7cb56a3d009f741463fb0ca0fb7997c1a090f/src/services/identityService.ts#L165

The last 3 methods are basically delegating to Veramo and then have specific support for JWKs

[nklomp]

Btw we also have a did jwk provider and resolver https://github.com/Sphereon-Opensource/ssi-sdk/tree/develop/packages/jwk-did-provider

[nickreynolds]

In our SSI Wallet we have code that actually has support to covert DID jwk and thus JWKs to hex. We intent to bring that to Veramo, but maybe you can already use it
Yes what you have seems to be essentially what this PR provides, with the addition of the p256 curve support, correct? Would love to bring that into Veramo

The did-jwk-provider also seems like it would help a lot with unit tests