feat: add async context manager support to ClientTransport (linter)

Author: cchinchilla-dev

src/a2a/client/transports/base.py

@@ -2,6 +2,13 @@
 
 from abc import ABC, abstractmethod
 from collections.abc import AsyncGenerator, Callable
+from typing import TYPE_CHECKING
+
+from typing_extensions import Self
+
+
+if TYPE_CHECKING:
+    from types import TracebackType
 
 from a2a.client.middleware import ClientCallContext
 from a2a.types import (
@@ -21,15 +28,15 @@
 class ClientTransport(ABC):
     """Abstract base class for a client transport."""
 
-    async def __aenter__(self) -> ClientTransport:
+    async def __aenter__(self) -> Self:
         """Enter the async context manager, returning the transport itself."""
         return self
 
     async def __aexit__(
         self,
         exc_type: type[BaseException] | None,
         exc_val: BaseException | None,
-        exc_tb: object | None,
+        exc_tb: TracebackType | None,
     ) -> None:
         """Exit the async context manager, ensuring close() is called."""
         await self.close()