Document ECDSA signature verification

[nicc]

Create a tutorial that steps through ECDSA signature verification. It shouod be based on the API defined in this issue.

See reference implementation using Circom: https://github.com/BigWhaleLabs/seal-hub-ecdsa-verifier-contract/blob/main/circuits/ECDSAChecker.circom

From Phil:
ECDSA is the elliptical cryptography scheme used by Ethereum. SnarkyJS can’t “read” things from Ethereum without having a custom gate for ECDSA. After we have ECDSA, SnarkyJS can allow people eg, to attest to the fact that they own a bored ape on Ethereum without doxxing themselves, or that they have an ETH balance of more than x. There may also be use cases outside Ethereum

[barriebyron]

I've circled in with Phil Kelly to find out what a use case looks like. thank you @Trivo25 for being my tutorial code partner to deliver the example code for https://github.com/o1-labs/docs2/tree/main/examples/zkapps

I am up for working on the content but do require engineering support for the command sequence and code

[barriebyron]

@Trivo25 thank you for being the example code hero!

[nicc]

This should start alongside #968 to parallelise and share context.

[barriebyron]

No doc work to do, yet
Here is a growing collection of resources:
SnarkyJS SHA/Keccak RFC design convo o1-labs/rfcs#9
SnarkyJS ECDSA RFC design convo o1-labs/rfcs#14

SnarkyJS PRs can merge only after crypto updates are in:
#999
#989
#988

Other resources
https://www.notion.so/minaprotocol/ECDSA-ver-gadget-PoC-PRD-9458c38adf204d6b922deb8eed1ac193
https://www.notion.so/minaprotocol/Ethereum-Primitives-Dependencies-21e56244b1cd43b1807aac39fdd25117
1.5 hour video ECDSA sync

page 11 of the nullifier PLUME paper for the SnarkyJS nullifier

2.2 Signatures
2.2.1 ECDSA
ECDSA is the signature protocol used by Bitcoin, Ethereum and most blockchain
systems [27, 7], due to both Schnorr’s copyright and ECDSA’s relatively smaller key
size, especially when compared to RSA. Most RSA keys are 2,048 bits, but the much
shorter 256-bit ECDSA key provides roughly equal security to a 3,248 bit RSA key
[30].
ECDSA uses the secp256k1 curve...
Because almost all existing blockchain and public key infrastructure uses this curve
for non-deterministic signatures, we are interested in a nullifier construction for this
class of curves specifically.

[barriebyron]

Doc outlined in draft PR o1-labs/docs2#562 and ready for dev contributions from @MartinMinkov or @Trivo25

[barriebyron]

@nicc I expected to find this issue in the https://github.com/o1-labs/docs2 repo... I don't see how to transfer it, as the author, are you able to move it?
I successfully moved an issue recently... maybe because I was the author? Can you try to move to the docs2 repo?