feat!: introduces multisignature abstractions in utils

[CiottiGiorgio]

No description provided.

[Copilot]

Pull Request Overview

This PR introduces multisignature abstractions in the AlgoKit utilities by adding a new multisig module and renaming existing signer classes to be more specific about their purpose. The changes support both key pair and multisig account signing patterns.

Key changes:

• Adds new multisig.rs module with MultisigAccount and related types
• Renames EmptySigner to EmptyKeyPairSigner and TestAccount to TestKeyPairAccount for clarity
• Introduces EmptyMultisigSigner for multisig transaction signing

Reviewed Changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
crates/algokit_utils/src/multisig.rs	New module defining multisig account abstractions and conversions
crates/algokit_utils/src/transactions/common.rs	Adds multisig signer implementation and renames existing signer
crates/algokit_utils/src/transactions/mod.rs	Updates exports to reflect renamed signer
crates/algokit_utils/src/transactions/composer.rs	Updates usage of renamed signer
crates/algokit_utils/src/testing/account_helpers.rs	Renames TestAccount to TestKeyPairAccount throughout
crates/algokit_utils/src/testing/fixture.rs	Updates to use renamed account type
crates/algokit_utils/src/testing/mod.rs	Updates exports to reflect renamed account type
crates/algokit_utils/src/lib.rs	Adds multisig module and updates public exports

Comments suppressed due to low confidence (1)

crates/algokit_utils/src/multisig.rs:45

• The struct MultisigSignature has the same name as the existing algokit_transact::MultisigSignature type used elsewhere in the codebase. This creates naming ambiguity and could lead to confusion. Consider renaming it to something more specific like MultisigSignatureBuilder or PartialMultisigSignature.

pub struct MultisigSignature {

[Copilot]

The MultisigSignature struct lacks documentation explaining its purpose and how it differs from algokit_transact::MultisigSignature. Add a docstring explaining when and how this struct should be used.

Suggested change

	/// Represents a multisignature with optional subsignatures for each participant.
	///
	/// This struct is distinct from `algokit_transact::MultisigSignature` in that it
	/// focuses on the subsignature details, allowing for partial or incomplete
	/// multisignatures. It is used when working with multisignature accounts where
	/// some participants may not have signed yet.
	///
	/// Use this struct when you need to manage or inspect the state of individual
	/// subsignatures in a multisignature account.

[Copilot]

The EmptyMultisigSigner struct lacks documentation explaining its purpose and intended use case. Add a docstring describing when this signer should be used and how it behaves.

Suggested change

	/// A signer implementation for multisignature accounts that produces placeholder signatures.
	///
	/// # Purpose
	/// This struct is intended for use in testing or scenarios where real signatures are not required.
	/// It creates a multisignature with empty subsignatures (`[0; ALGORAND_SIGNATURE_BYTE_LENGTH]`).
	///
	/// # Behavior
	/// When signing transactions, it populates the multisignature with placeholder subsignatures
	/// and does not produce a valid cryptographic signature. This makes it unsuitable for
	/// production use but useful for testing or as a placeholder.

[Copilot]

Setting all subsignatures to zero bytes creates an invalid multisig signature. This could be misleading for testing purposes. Consider adding a comment explaining that this creates dummy signatures for testing, or provide a way to create valid empty signatures.

Suggested change

	multisig
	.subsignatures
	.iter_mut()
	.for_each(|subsig| subsig.signature = Some([0; ALGORAND_SIGNATURE_BYTE_LENGTH]));
	// Set dummy signatures for testing purposes. These are not valid signatures
	// and should only be used in non-production scenarios.
	multisig
	.subsignatures
	.iter_mut()
	.for_each(|subsig| subsig.signature = Some(Self::generate_dummy_signature()));