v0.2.1rc1

Feature: Model Override and Core Improvements

• Model Override Capability: Introduced model override functionality for GenerateTemplate and ToolingTemplate. This allows for specifying a different model for individual templates, enabling cost and performance optimization.
• Enhanced Jinja2 Error Handling: Improved Jinja2 template error handling by adding a disable_jinja option. This is useful when template content includes Jinja syntax that should not be rendered.
• Subroutine Environment Isolation: Implemented complete environment isolation for SubroutineTemplate, ensuring subroutines run in a clean context without affecting the parent session.
• Runner Model Handling: Refactored runner model handling for better consistency and clarity across the framework.
• Design Documentation: Added comprehensive design documentation for template model override, detailing its benefits, usage, and implementation.
• Examples Update: Updated examples to showcase new features and improve overall code structure, providing clearer usage patterns.

Refactor: End Conversation Flow

• Removed JumpTemplate: Removed JumpTemplate to simplify conversation flow control. Navigation logic should be handled by control flow templates and session state.
• Enhanced EndTemplate: Improved EndTemplate to support optional farewell messages, providing a more graceful way to end conversations.
• Simplified Runner: Runner implementation is simplified by removing start_template_id, streamlining the execution process.
• EndConversationTool: Added EndConversationTool to allow LLMs to explicitly end conversations, with support for farewell messages.
• Design Documentation: Added design documentation for EndConversationTool, outlining its purpose, usage, and integration within the framework.

Feature: Event Handling and Core Refactoring

• Event Handling System: Implemented a new event handling system, introducing UserInteractionEvent for managing user inputs and interactions within templates.
• Core Component Refactoring: Refactored core components to enhance maintainability and scalability, improving the internal structure of the framework.
• Session Transformer Renaming: Renamed session transformers for improved clarity and consistency in naming conventions.
• Design Proposal: Added a design proposal document for the event handling system, detailing its architecture, benefits, and future extensions.

Feature: API Runner with FastAPI Integration

• APIRunner: Introduced a new APIRunner class, providing seamless integration with FastAPI to expose agents as RESTful APIs.
• FastAPI Integration: Implemented REST endpoints for session creation, status retrieval, input posting, and session starting, facilitating web-based agent interaction.
• Session Management: Added robust session management capabilities within APIRunner to handle multiple concurrent conversations.
• Async Support: Ens