feat(secp256k1): implement public key recovery in secp256k1 unit tests

[mohd-kashif]

Ticket: WIN-7654

enhance signature creation and recovery with secp256k1 package for sdk-coin-flrp and added related test cases

[Copilot]

Pull Request Overview

This PR implements public key recovery functionality for secp256k1 signatures to support the FLRP coin implementation. The changes add signature recovery capabilities using the secp256k1 package, enabling verification of signatures by recovering the public key from the signature and message.

Key Changes

• Added recoverPublicKey method to the secp256k1 module with validation for message hash length, signature format, and recovery parameter
• Enhanced signature creation in utils.ts to include recovery parameter (creating 65-byte signatures instead of 64-byte)
• Implemented recoverySignature method to recover public keys from signatures with proper message hashing

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
modules/secp256k1/src/index.ts	Adds recoverPublicKey method with input validation for hash length, signature format, and recovery parameter
modules/secp256k1/test/index.ts	Comprehensive test suite for public key recovery covering compressed/uncompressed formats and error cases
modules/sdk-coin-flrp/src/lib/utils.ts	Updates createSignature to append recovery parameter and implements recoverySignature to extract and use it
modules/sdk-coin-flrp/test/unit/lib/utils.ts	Test cases validating signature recovery functionality and error handling

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[Copilot]

Pull Request Overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

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[shenbenson]

@claude can you explain this PR and provide a review?

[mohd-kashif]

@claude can you explain this PR and provide a review?

@shenbenson claude review is not enabled on SDK PRs. you can refer to this copilot review --> #7301 (review)