chore(cli,standard-tests,text-splitters): fix some ruff TC rules (#33934)

Co-authored-by: Mason Daugherty <mason@langchain.dev>

libs/standard-tests/tests/unit_tests/custom_chat_model.py

@@ -1,9 +1,7 @@
 from __future__ import annotations
 
-from collections.abc import Iterator
-from typing import Any
+from typing import TYPE_CHECKING, Any
 
-from langchain_core.callbacks import CallbackManagerForLLMRun
 from langchain_core.language_models import BaseChatModel
 from langchain_core.messages import AIMessage, AIMessageChunk, BaseMessage
 from langchain_core.messages.ai import UsageMetadata
@@ -11,6 +9,11 @@ from langchain_core.outputs import ChatGeneration, ChatGenerationChunk, ChatResu
 from pydantic import Field
 from typing_extensions import override
 
+if TYPE_CHECKING:
+    from collections.abc import Iterator
+
+    from langchain_core.callbacks import CallbackManagerForLLMRun
+
 
 class ChatParrotLink(BaseChatModel):
     """Chat Parrot Link.