Comprehensive Type Hint Improvements Across the SDK #36

[manny-uncharted]

Closes out: #36

Implementation Plan:

Core SDK Class:

• Add return types to all methods
• Type all instance variables
• Add docstrings with type information
• Implement proper generic types

Model Classes:

• Add type variables for generic containers
• Implement protocols for common interfaces
• Add return types to all methods
• Type all instance variables

Utility Functions:

• Add proper type hints to all utility functions
• Use Union types where appropriate
• Add Literal types for string constants

Configuration:

• Add mypy configuration file
• Set strict type checking options
• Configure type checking in CI/CD