feat(info): add extra agents info method

[hubertkirch]

Description

This change introduces the extraAgents method to the Info class. This method allows for the retrieval of extra agents associated with a user and includes a comprehensive test suite to validate the response. The implementation adheres to the existing API patterns and documentation standards of the project.

Related Issue

Closes #205

Type of Change

• New feature (non-breaking change which adds functionality)
• Bug fix (non-breaking change which fixes an issue)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Other... Please describe: