[Backend] backend schema setup & doc

[ChenBingWei1201]

What is this PR for?

• setup backend schema
• add the guide of the backend development into README
• docker-compose.yml

What type of PR is it?

[Feature | Documentation]

Todos

• [x] README
• [x] docker-compose
• [x] Prisma Schema
• [x] Prettier
• [x] Eslint

What is the GitHub issue?

close #43

How should this be tested?

apollo graphql

Screenshots (if appropriate)

N/A

Questions:

• Do the license files need updating? No
• Are there breaking changes for older versions? Yes
• Does this need new documentation? Yes

[ChenBingWei1201]

LGTM

[ChenBingWei1201]

Additionally, maybe I will try to use express & prisma for backend and react-query for frontend, because some unknown problems occurred when I built up my wp final project with apollo server and apollo client. Most of them violate the Rules of Hooks. I haven't found any solution to it. See #46