fix: implement encryption based on XMTP but using noble

[pcarranzav]

Fixes #90

[cmwhited]

good find. and who doesn't love one less dep

[nikgraf]

Code looks good from my perspective. One thing I would do to be 100% certain is

1. add @xmtp/xmtp-js as devDependency
2. add a test to encrypt with our function and decrypt with xmtp
3. add a test to encrypt with xmtp and decrypt with our function

This way we can be very certain that this is correct. Do you think it's worth it?

[pcarranzav]

The problem is xmtp-js was breaking our tests because of the weird issue on webcrypto.subtle. Their serialization/deserialization after encryption is also different than ours so it would take a bit of wrangling. So I think it would be a good idea but considering the tradeoffs I would prefer not to add that test for now. Once we're closer to a release version we can work with the Foundation to set up an external security review. Does that sound reasonable?

[nikgraf]

ah right, didn't think about the test not working 🤦 In this case my suggestion makes no sense.