- Created DocusignEnvelopeRequest.cls (separate global class for input)
- Created DocusignEnvelopeResult.cls (separate global class for output)
- Updated DocusignCompositeEnvelopeBuilder to use standalone classes
- Updated DocusignEnvelopeRequestHandler to reference standalone classes
- Updated all test classes to use new class references
- Fixes Flow Builder visibility issues with nested inner classes
- Better API design with clear input/output types
- Easier to extend and reuse across other classes