anthropic[patch]: add kwargs to format_output base (#18715)

_generate() and _agenerate() both accept **kwargs, then pass them on to
_format_output; but _format_output doesn't accept **kwargs. Attempting
to pass, e.g.,

     timeout=50

to _generate (or invoke()) results in a TypeError.

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---------

Co-authored-by: Erick Friis <erick@langchain.dev>

libs/partners/anthropic/langchain_anthropic/chat_models.py

@@ -263,7 +263,11 @@ class ChatAnthropic(BaseChatModel):
                     await run_manager.on_llm_new_token(text, chunk=chunk)
                 yield chunk
 
-    def _format_output(self, data: Any) -> ChatResult:
+    def _format_output(
+        self,
+        data: Any,
+        **kwargs: Any,
+    ) -> ChatResult:
         return ChatResult(
             generations=[
                 ChatGeneration(message=AIMessage(content=data.content[0].text))
@@ -285,7 +289,7 @@ class ChatAnthropic(BaseChatModel):
             return generate_from_stream(stream_iter)
         params = self._format_params(messages=messages, stop=stop, **kwargs)
         data = self._client.messages.create(**params)
-        return self._format_output(data)
+        return self._format_output(data, **kwargs)
 
     async def _agenerate(
         self,
@@ -301,7 +305,7 @@ class ChatAnthropic(BaseChatModel):
             return await agenerate_from_stream(stream_iter)
         params = self._format_params(messages=messages, stop=stop, **kwargs)
         data = await self._async_client.messages.create(**params)
-        return self._format_output(data)
+        return self._format_output(data, **kwargs)
 
 
 @deprecated(since="0.1.0", removal="0.2.0", alternative="ChatAnthropic")