docs: Getting started guide from end user perspective

[mkbhanda]

This should leverage published docker images for ease of use and be organized to help someone do a quick PoC.
Include steps on what to expect in terms of containers, ready status, reaching the individual services.

Let the instructions focus on a single node install.

Then get deeper into customizing a rag pipeline, and finally evaluating the same.
These can wait.

Advanced steps could be running on Kubernetes using a helm chart and even more advanced using Kubernetes with GMC.