docs[patch]: Fix docs bugs in response to feedback (#23649)
- Update Meta Llama 3 cookbook link
- Add prereq section and information on `messages_modifier` to LangGraph
migration guide
- Update `PydanticToolsParser` explanation and entrypoint in tool
calling guide
- Add more obvious warning to `OllamaFunctions`
- Fix Wikidata tool install flow
- Update Bedrock LLM initialization
@baskaryan can you add a bit of information on how to authenticate into
the `ChatBedrock` and `BedrockLLM` models? I wasn't able to figure it
out :(
