Simple app documentation is out of date

[xtreme-sameer-vohra]

Readme mentions building a single docker container for which there is no Dockerfile resulting in

% docker build -t simple-reasoning-agent:latest .
[+] Building 0.1s (1/1) FINISHED                                                                                docker:desktop-linux
 => [internal] load build definition from Dockerfile                                                                            0.0s
 => => transferring dockerfile: 2B                                                                                              0.0s
ERROR: failed to solve: failed to read dockerfile: open Dockerfile: no such file or directory

Instead I believe the current workflow is

docker compose up --build

[sabbyanandan]

Hi, @xtreme-sameer-vohra! 😄

Good catch. The Dockerfile inside each [nextjs-client](https://github.com/8090-inc/xrx-sample-apps/tree/main/simple-app/nextjs-client) folder can work with this instruction, but the README is wrong in its current state. Besides, it is much better to advertise just the Docker Compose, so I agree with you.

Do you want to take a stab at cleaning this up via a PR, Sameer?