Create SafeWebAuthnSignerProxy

[akshay-ap]

Fixes #312

Changes in PR:

• Create SafeWebAuthnSignerSingleton. This contract has no storage, no immutables, and no constants.

• Create SafeWebAuthnSignerProxy and corresponding proxy factory i.e. SafeWebAuthnSignerProxyFactory

• Create immutable singleton contract when deploying proxy factory

• SafeWebAuthnSignerProxyFactory.isValidSignatureForSigner(...) forwards to singleton contract instead directly calling WebAuthn library

• SafeWebAuthnSignerProxy uses no storage to avoid 4337 storage access restriction violation.

• Add unit test to verify that SafeWebAuthnSignerProxy forwards every call to singleton address

• Report gas usage metrics

• Update github workflow to execute benchmarking tests separately. (This is required to get accurate gas usage numbers)

• Update documentation

• Replace SafeWebAuthnSigner with SafeWebAuthnSignerProxy, same for factory contract

• Update all tests to use SafeWebAuthnSignerProxy. Hence, the large diff in this PR.

Benchmark number from this PR:

Gas Benchmarking Proxy [@bench]
    SafeWebAuthnSignerProxy
      ⛽ deployment: 164012
      ✔ Benchmark signer deployment cost (10[38](https://github.com/safe-global/safe-modules/actions/runs/8739938588/job/23982409583?pr=370#step:4:39)ms)
      ⛽ verification (FreshCryptoLib): 216248
      ✔ Benchmark signer verification cost with FreshCryptoLib verifier (201ms)
      ⛽ verification (daimo-eth): 346151
      ✔ Benchmark signer verification cost with daimo-eth verifier (186ms)
      ⛽ verification (Dummy): 14[40](https://github.com/safe-global/safe-modules/actions/runs/8739938588/job/23982409583?pr=370#step:4:41)2
      ✔ Benchmark signer verification cost with Dummy verifier

Benchmark number from main:

  Gas Benchmarking [@bench]
    SafeWebAuthnSigner
      ⛽ deployment: 491288
      ✔ Benchmark signer deployment cost (654ms)
      ⛽ verification (FreshCryptoLib): 209630
      ✔ Benchmark signer verification cost with FreshCryptoLib verifier (138ms)
      ⛽ verification (daimo-eth): 336881
      ✔ Benchmark signer verification cost with daimo-eth verifier (108ms)
      ⛽ verification (Dummy): 11266
      ✔ Benchmark signer verification cost with Dummy verifier

[coveralls]

Pull Request Test Coverage Report for Build 8784802120

Details

• 16 of 16 (100.0%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-13.3%) to 86.747%

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Totals
Change from base Build 8783507331:	-13.3%
Covered Lines:	111
Relevant Lines:	118

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💛 - Coveralls

[nlordell]

@akshay-ap - can you rebase the PR, it would help with the review process.

[nlordell]

I noticed when running locally that there are compiler warning that can be resolved.