[Feature request] Langchain Support - Chat Model

[raymon-io]

🚀 The feature, motivation and pitch

Requesting to support Langchain by creating a ChatModel for Langchain. Since Torchchat already supports OpenAI compatible chat apis they should be very similar to chat models like ChatOllama, ChatLlamaCpp.

I know this has to be done in Langchain's repository and I created a discussion there but it would be great if someone knowledgeable in both Langchain and TorchChat is willing to take initiative on it.

[Jack-Khuu]

Good call out, with the recent OpenAI API polished in TC, this can be an easy win

cc: @vmpuri