Signatures: support lmsig logicsig signatures

[cce]

Based on algorand/js-algorand-sdk#999 and algorand/py-algorand-sdk#579

[Copilot]

Pull Request Overview

This PR adds support for "lmsig" (logicsig multisig signatures) to the Algorand SDK, expanding the existing signature types beyond just regular signatures ("sig") and legacy multisig signatures ("msig"). The implementation allows logic signatures to be signed by multisig addresses with proper verification and encoding support.

Key changes include:

• Added new lmsig field and signature counting logic to LogicsigSignature
• Updated account classes to handle the new signature type
• Modified signature verification to use multisig-specific signing data

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/main/java/com/algorand/algosdk/crypto/LogicsigSignature.java	Adds lmsig field, sigCount method, and multisig-specific verification logic
src/main/java/com/algorand/algosdk/account/LogicSigAccount.java	Updates constructors and address resolution to support lmsig signatures
src/main/java/com/algorand/algosdk/account/Account.java	Modifies logicsig signing methods to use lmsig instead of legacy msig
src/test/java/com/algorand/algosdk/account/TestLogicSigAccount.java	Updates tests to verify lmsig functionality and expected serialization
src/test/java/com/algorand/algosdk/crypto/TestLogicsigSignature.java	Adds assertion for lmsig field in multisig test
src/test/resources/msig_delegated.txn	Test vector for lmsig delegated transaction
src/test/resources/msig_delegated_other.txn	Test vector for lmsig delegated transaction with different sender

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