Support additional content types in post requests

🚀 Feature

Add support to additional content-type requests such as application/octet-stream

Motivation

It will make the Litserv more flexible. It will also allow streaming binary data.

Pitch

Basically add another option to the lines here https://github.com/Lightning-AI/LitServe/blob/c8cf6b224d68bbf2006b4b20198007ead3a58fd8/src/litserve/server.py#L351

that returns request.body()

if self.request_type == Request:
        if request.headers["Content-Type"] == "application/x-www-form-urlencoded" or request.headers[
            "Content-Type"
        ].startswith("multipart/form-data"):
            payload = await request.form()
        elif request.headers["Content-Type"] == "application/octet-stream":
            payload = await request.body()
        else:
            payload = await request.json()

to support the following request

response = requests.post(API_URL, data = input_bytes, headers = {"Content-Type": "application/octet-stream"})

Alternatives

Additional context

Start in src/litserve/server.py at the request-handling code around the linked line, and trace how Content-Type selects the request parser. Add support for application/octet-stream so the request body is returned as bytes, then verify that a binary POST using that content type is accepted.