[feat] Redirect / to docs page

@ngpollock the reason for the "not found" errors is that you're trying to access localhost:8000/, but currently, there's nothing running on that endpoint (/.

You should use the endpoints provided in the documentation, like /ocr/request

https://github.com/CatchTheTornado/text-extract-api

@pkarw this leads me to consider that it might be worth route / to docs page, or if its not easy in FastAPI then do redirect from / to docs ;)

_Originally posted by @choinek in https://github.com/CatchTheTornado/text-extract-api/discussions/78#discussioncomment-11821392_

Start by locating the FastAPI application entry point and the existing root route, then check how the documentation endpoint is configured. Done means requesting / redirects to the docs page without changing the documented API endpoints.

Written by the indexing model from the issue text.