Use new CBOR wrappers in COSE verifier

[maxtropets]

Towards #7542.

[Copilot]

Pull request overview

This pull request refactors the COSE verifier implementation to use new CBOR wrapper functions instead of raw QCBOR API calls, improving code maintainability and error handling.

Changes:

• Replaced manual QCBOR decoding with higher-level CBOR wrapper API calls in two functions
• Simplified error handling using rethrow_with_msg helper for better context in error messages
• Removed significant boilerplate QCBOR code in favor of cleaner API

Comments suppressed due to low confidence (1)

src/crypto/openssl/cose_verifier.cpp:26

• The function qcbor_buf_to_string appears to be unused after the refactoring. Consider removing it to eliminate dead code.

  std::string qcbor_buf_to_string(const UsefulBufC& buf)
  {
    return {reinterpret_cast<const char*>(buf.ptr), buf.len};
  }

[Copilot]

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (1)

src/crypto/openssl/cose_verifier.cpp:26

• The qcbor_buf_to_string function is no longer used after the refactoring to use new CBOR wrappers. This unused function should be removed to improve code maintainability.

  std::string qcbor_buf_to_string(const UsefulBufC& buf)
  {
    return {reinterpret_cast<const char*>(buf.ptr), buf.len};
  }