Improve error handling in coordinator agent JSON parsing

[SL-Mar]

Summary

Replaced bare except clause with specific json.JSONDecodeError exception handling in the coordinator agent's execution plan creation method.

Key Changes

• Changed generic except: to except json.JSONDecodeError: in _create_execution_plan() method
• This improves error specificity and follows Python best practices by only catching the intended exception type

Implementation Details

The bare except clause was catching all exceptions indiscriminately, which could mask unexpected errors and make debugging difficult. By catching only json.JSONDecodeError, the code now:

• Explicitly handles JSON parsing failures with the fallback default plan
• Allows other unexpected exceptions to propagate for proper error reporting
• Improves code clarity and maintainability
• Aligns with PEP 8 guidelines against bare except clauses