QA/3 Improve readme of the project

[ali-nasir-ali]

The current readme of the project is the generic setup of FP projects. We should replace that with a more specific one tailored to this project itself.

This should include:

1. What this project is about, what does it do
2. How to set up the project locally, what setup people need to take (like what .env files they need to create, etc).
3. How to set up the database locally - similar to point (2), we used to have a schema in the repository that could be used to fill in the database with the starting set of schema and data, but somehow(?) this got removed from the repo. This is an important piece of stuff so let's put it back. Might want to clean it up along the way
4. How to run and test the application locally.
5. How to set up and deploy the application to Render.

Anything CYF specific and not relevant to this project should be removed

[ali-nasir-ali]

#56