add: more example endpoints

[cdscih]

It'd be great to have an example folder, on the top level of the project, where to put inside a docker-compose which exposes 3 endpoints:

• one hat retrieves data from a postgres
• one that does the same but adds a Redis cache on top of it
• one that retrieves data from a mongodb

I'm gonna to try to do one written in Golang as well.

[cdscih]

I added a python server that covers raw postgres vs redis cache use case.

I don't think we need a mongodb one but it'd be fun to add a Golang and perhaps a Bun one in the future.