HELP WANTED - Update langgraph docs tutorials

[casparb]

Privileged issue

• I am a LangGraph maintainer, or was asked directly by a LangGraph maintainer to create an issue here.

Issue Content

Related issue: #6332

There are a handful of old imports that need to be updated in langgraph/docs e.g.:

# incorrect:
from langchainhub import pull 

correct would be to import langsmith client: docs

Also need to clean up references to old types like FunctionMessage -> ToolMessage

Would be good for somebody to identify all old imports and types and do a big replace-all in .ipynb files.

For whoever is interested - before you submit a PR, please drop a report of the changes you'll be making here and I'll approve them (to save you some time).

[hinthornw]

For hub haven't we recommended using the langsmith client directly? Or is that no longer recommended

[smitdhakecha]

Hi @casparb is this issue still relevant? I can take a look. Confirming before I start.