This pull request introduces significant updates to enhance call configuration flexibility and improve handler functionality in the conformance framework. The key changes include the introduction of a new CallOptions class for managing call-specific options like timeouts and abort events, updates to handler methods to include a HandlerContext for richer context management, and adjustments to client and server implementations to integrate these enhancements.

Call Configuration Enhancements:

• Added a new CallOptions class in src/connect/call_options.py to encapsulate per-call configuration, including timeout and abort event support. This provides a cleaner and more flexible way to manage call-specific options.
• Updated the Client class in src/connect/client.py to accept CallOptions in both _call_unary and _call_stream methods, enabling the use of the new configuration options.

Handler Context Integration:

• Introduced HandlerContext to handler methods in conformance/gen/connectrpc/conformance/v1/conformancev1connect/service_connect.py, allowing access to additional context like remaining timeout.
• Updated server-side handlers in conformance/server.py to utilize HandlerContext for calculating timeout values dynamically and to improve request handling. [1] [2] [3]

Refactoring and Interceptor Updates:

• Replaced Interceptor with HandlerInterceptor in examples/server.py to align with the new handler context implementation, ensuring compatibility with the updated call flow.
• Adjusted the wrap_unary method in examples/server.py to pass HandlerContext to the next function in the interceptor chain.

Streamlining Call Usage:

• Refactored StreamRequest usage in conformance/client_runner.py to separate CallOptions from the request object, improving readability and modularity. [1] [2] [3]

These changes collectively enhance the flexibility, maintainability, and clarity of the conformance framework while introducing new capabilities for managing call-specific configurations.