Remove langchain-community from dependencies if it's not used #5914
Description
We had a non-obvious conflict — pip was only warning about it rather than failing. The chain was: langchain-community==0.4.1 → dataclasses-json==0.6.7 → marshmallow>=3.18.0,<4.0.0. uv's strict resolver caught this transitive conflict that pip silently ignored.
I'll file a follow-up issue to remove langchain-community, as I don't think it's actually needed.
Originally posted by @suhaibmujahid in #5913 (comment)