chore(docs): Consolidate hooks for copy markdown and notebooks (#5459)

Consolidating the hooks to avoid duplication of logic

We need this change for consolidating js and python content: we need include-markdown to run as a mkdocs plugin before our pipeline (rather than as markdown extension which runs after our hooks plugin).

docs/docs/tutorials/get-started/2-add-tools.md

@@ -73,7 +73,7 @@ For the `StateGraph` you created in the [first tutorial](./1-build-basic-chatbot
 
 Let's first select our LLM:
 
-{!snippets/chat_model_tabs.md!}
+{% include-markdown "../../../snippets/chat_model_tabs.md" %}
 
 <!---
 ```python
@@ -286,7 +286,7 @@ For ease of use, adjust your code to replace the following with LangGraph prebui
 - `BasicToolNode` is replaced with the prebuilt [ToolNode](https://langchain-ai.github.io/langgraph/reference/prebuilt/#toolnode)
 - `route_tools` is replaced with the prebuilt [tools_condition](https://langchain-ai.github.io/langgraph/reference/prebuilt/#tools_condition)
 
-{!snippets/chat_model_tabs.md!}
+{% include-markdown "../../../snippets/chat_model_tabs.md" %}
 
 
 ```python hl_lines="25 30"