Python: [BREAKING] Renamed next middleware parameter to call_next (#3735)

* Renamed next middleware parameter to call_next

* Resolved comments

python/samples/getting_started/middleware/chat_middleware.py

@@ -57,7 +57,7 @@ class InputObserverMiddleware(ChatMiddleware):
     async def process(
         self,
         context: ChatContext,
-        next: Callable[[ChatContext], Awaitable[None]],
+        call_next: Callable[[ChatContext], Awaitable[None]],
     ) -> None:
         """Observe and modify input messages before they are sent to AI."""
         print("[InputObserverMiddleware] Observing input messages:")
@@ -91,7 +91,7 @@ class InputObserverMiddleware(ChatMiddleware):
         context.messages[:] = modified_messages
 
         # Continue to next middleware or AI execution
-        await next(context)
+        await call_next(context)
 
         # Observe that processing is complete
         print("[InputObserverMiddleware] Processing completed")
@@ -100,7 +100,7 @@ class InputObserverMiddleware(ChatMiddleware):
 @chat_middleware
 async def security_and_override_middleware(
     context: ChatContext,
-    next: Callable[[ChatContext], Awaitable[None]],
+    call_next: Callable[[ChatContext], Awaitable[None]],
 ) -> None:
     """Function-based middleware that implements security filtering and response override."""
     print("[SecurityMiddleware] Processing input...")
@@ -131,7 +131,7 @@ async def security_and_override_middleware(
                     raise MiddlewareTermination
 
     # Continue to next middleware or AI execution
-    await next(context)
+    await call_next(context)
 
 
 async def class_based_chat_middleware() -> None: