Add Keccak-256, ECDSA support, and tests

[BlobMaster41]

Description

Bump package to v1.11.0-rc.5 and add a native Keccak-256 implementation and test suite. Export keccak helpers from runtime/index and add keccak256, keccak256Concat, functionSelector, ethAddressFromPubKey, and low-level rot64 utilities. Extend signature handling: add ECDSA to SignaturesMethods, introduce verifyECDSASignature/internalVerifyECDSA and secp256k1 public-key validation, and update Blockchain.verifySignature to accept an explicit signatureType (with consensus checks, deprecation warnings, and error handling). Small API/behavior change in ExtendedAddress: use Revert for tweakedPublicKey validation. Includes comprehensive as-pect tests for keccak256 and rotation helpers.

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Performance improvement
• Refactoring (no functional changes)
• Documentation update
• CI/CD changes
• Dependencies update

Checklist

Build & Tests

• npm install completes without errors
• npm test passes all tests

Code Quality

• Code follows the project's coding standards
• No new compiler warnings introduced
• Error handling is appropriate
• SafeMath used for all arithmetic operations

Documentation

• Code comments added for complex logic
• Public APIs are documented
• README updated (if applicable)

Security

• No sensitive data (keys, credentials) committed
• No new security vulnerabilities introduced
• No floating-point arithmetic used

OPNet Specific

• Changes are compatible with existing smart contracts
• WASM execution behavior is unchanged (or documented if changed)
• Storage pointer allocation is correct
• Reentrancy considerations addressed

Testing

Related Issues

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