Sig nonce fix

[EugeneDrpc]

No description provided.

[Copilot]

Pull request overview

This PR fixes response signature wrapping for proto3 uint64 nonces represented as Java/Kotlin long, ensuring nonces with the high bit set (≥ 2^63) are formatted as unsigned decimal so signature verification can reconstruct the exact wrapped message.

Changes:

• Format the nonce component of the wrapped message using unsigned decimal (Long.toUnsignedString).
• Document the unsigned-uint64 nonce expectation and why it matters for signature verification.
• Add a regression test asserting nonces with the high bit set are wrapped without a negative sign.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
src/main/kotlin/io/emeraldpay/dshackle/upstream/signature/RsaSigner.kt	Switch nonce formatting to unsigned decimal in wrapMessage and document the uint64↔long behavior.
src/test/groovy/io/emeraldpay/dshackle/upstream/signature/RsaSignerSpec.groovy	Add a test case covering wrap behavior for nonces ≥ 2^63.

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[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.