Add update for langchain example

[AdamWozniewski]

Add update for LangChain example

[priley86]

We have a few conflicts here.

our current auth0-ai-langchain relies on langgraph >=0.5.3, <0.6.0.
our current auth0-fastapi==1.0.0b4 depends on fastapi>=0.115.11,<0.116.0

Also seeing that langgraph-cli[inmem] is also currently confilcting:

And because langgraph-cli[inmem]==0.4.2 depends on langgraph-api>=0.3
      and only langgraph-cli[inmem]<=0.4.2 is available, we can conclude that
      langgraph-cli[inmem]>=0.4.2 depends on langgraph-api>=0.4.7.
      And because your project depends on langgraph-api==0.2.102 and
      langgraph-cli[inmem]>=0.4.2, we can conclude that your project's requirements
      are unsatisfiable.

Preference here would be to keep current supported versions of those for now, and target this langgraph upgrade with a separate ticket / PR to the auth0-ai-python core first.

[priley86]

Not positive here w/ these. We will have to again test after backend langgraph SDK updates though.

[priley86]

proposal here would be to hold this PR for future w/ auth0-ai-python alongside updates. I think async auth updates can be covered alongside #15 for now.

[AdamWozniewski]

Good idea, this will help avoid the same thing as pr:
PR