Optimistic signature verification for signed batch info

[vusirikala]

Description

This PR implements optimistic signature verification to reduce the time required to verify SignedBatchInfo. When the optimistic signature verification feature flag is enabled, we will not verify these messages up front. We will accumulate the unverified messages, and when the accumulated voting power is higher than a threshold, we will aggregate all the signatures and verify the aggregated signature. If the verification fails, we need to verify each individual signature. The ValidatorVerifier stores the list of authors that submitted bad messages, and will disable the optimistic signature verification for these malicious voters.

Type of Change

• [ ] New feature
• [ ] Bug fix
• [ ] Breaking change
• [x] Performance improvement
• [ ] Refactoring
• [ ] Dependency update
• [ ] Documentation update
• [ ] Tests

Which Components or Systems Does This Change Impact?

• [x] Validator Node
• [ ] Full Node (API, Indexer, etc.)
• [ ] Move/Aptos Virtual Machine
• [ ] Aptos Framework
• [ ] Aptos CLI/SDK
• [ ] Developer Infrastructure
• [ ] Other (specify)

How Has This Been Tested?

Key Areas to Review

Checklist

• [ ] I have read and followed the CONTRIBUTING doc
• [ ] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I identified and added all stakeholders and component owners affected by this change as reviewers
• [ ] I tested both happy and unhappy path of the functionality
• [ ] I have made corresponding changes to the documentation