Make signer param optional in toMetaMaskSmartAccount

[jeffsmale90]

📝 Description

This PR implements the changes described in issue #163, making the signer parameter optional in the toMetaMaskSmartAccount function. This allows for the creation of smart account instances that can perform non-signing operations without requiring a signer to be provided.

🔄 What Changed?

List the specific changes made:

• packages/smart-accounts-kit/src/types.ts: Made the signer property optional in ToMetaMaskSmartAccountParameters.
• packages/smart-accounts-kit/src/signer.ts: Overloaded resolveSigner to accept an optional signer and return null if no signer is provided.
• packages/smart-accounts-kit/src/toMetaMaskSmartAccount.ts:
  • Added checks for signer existence before performing signDelegation and signUserOperation.
  • Introduced stub signer methods (signMessage, signTypedData, getStubSignature) that throw descriptive errors when called without a provided signer.
• packages/smart-accounts-kit/test/toMetaMaskSmartAccount.test.ts: Added 8 new test cases to cover:
  • Creating smart accounts for all implementations without a signer.
  • Verifying non-signing operations (getAddress, encodeCalls) work correctly.
  • Ensuring signing operations (signUserOperation, signDelegation) throw appropriate errors when no signer is present.

🚀 Why?

Explain the motivation behind these changes:

• To allow users to create MetaMaskSmartAccount instances for operations that do not require a signer (e.g., fetching address, encoding calls), reducing boilerplate and improving flexibility.
• To provide clear error messages when signing operations are attempted on a smart account created without a signer.

🧪 How to Test?

Describe how to test these changes:

• Manual testing steps:
  1. Run the existing test suite.
  2. Verify that toMetaMaskSmartAccount can be called without providing a signer parameter.
  3. Confirm that methods like getAddress() and encodeCalls() work correctly on such accounts.
  4. Confirm that methods like signUserOperation() and signDelegation() throw the expected error when called on an account created without a signer.
• Automated tests added/updated
• All existing tests pass

⚠️ Breaking Changes

List any breaking changes:

• No breaking changes
• Breaking changes (describe below):

📋 Checklist

Check off completed items:

• Code follows the project's coding standards
• Self-review completed
• Documentation updated (if needed)
• Tests added/updated
• Changelog updated (if needed)
• All CI checks pass

🔗 Related Issues

Link to related issues:
Closes #163

📚 Additional Notes

None.

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Slack Thread

  

[cursor]

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[jeffsmale90]

One concern - otherwise this looks really good.