End-to-end fixes for agentic identities

[rodrigobr-msft]

This pull request introduces important improvements to the authentication and token handling logic throughout the Microsoft Agents hosting core, as well as enforces stricter conversation ID length constraints in connector client methods. The changes refactor how UserTokenClient and ConnectorClient instances are created, ensuring that the TurnContext is consistently provided, and enhance error handling and validation for agentic requests. Additionally, new environment and requirements files are added for agentic test samples.

Authentication and Token Handling Improvements

• Refactored the creation of UserTokenClient and ConnectorClient instances in channel_service_adapter.py to require the TurnContext and store the token client in context.turn_state, improving context-aware authentication and ensuring proper token handling for agentic and user flows. [1] [2] [3] [4]
• Updated the abstract methods in channel_service_client_factory_base.py to require the TurnContext parameter for both create_connector_client and create_user_token_client, enforcing context-aware client creation throughout the codebase. [1] [2]
• Refactored rest_channel_service_client_factory.py to split agentic token retrieval into a dedicated _get_agentic_token method, improve error handling, and require both context and claims_identity for client creation. Enhanced validation and logging for agentic and user token acquisition. [1] [2] [3] [4] [5]

Conversation ID Length Enforcement

• Added logic to all relevant methods in connector_client.py to truncate conversation_id to a maximum of 200 characters before using it in API calls, preventing potential errors due to overly long IDs. [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11]

Test Sample Setup

• Added a template environment file and requirements for agentic test samples, enabling easier configuration and setup for agentic authorization and connection mapping. [1] [2]

[cleemullins]

Looks great. Minor comments. I would change the truncation of the conversationId to a single method (normalizeConversationId) and allow it to be changed/overriden without needing a major change in the code.