Fix ChatGPT API endpoint

[AlexCheema]

Currently doesn't work - which means the only way to access inference is via peer handles in Python, which isn't very user-friendly for applications to add a new library.

[AlexCheema]

One of the issues here is that since we don't treat any node as a "master" or "worker" (all nodes are equal), the "head" and "tail" nodes are dynamic. However, the prompt needs to be sent to the "head" and the tokens are received by the "tail".

We could hack this by breaking the p2p equality assumption, but that would need to be fixed down the line.

The better thing is to:

• forward the prompt until you hit the "head" (this should be fairly simple).
• forward API requests to the "tail" that has all the generated tokens (this sounds hard and hacky). The other thing we can do is only serve the API from the "tail"

[AlexCheema]

Fixed the former: 1d5c28a
The latter is harder and for now, we'll only support API requests to the "tail". You can always force a node to be the "tail" by specifying its node-id to be sorted last e.g. with python3 main.py --node-id "xxx-node"

[AlexCheema]

Fixed in f2895cb