Refactor to use FastAPI

[petechd]

What is the context of this PR?

To improve validator performance we want to use a framework that supports concurrency. Mainly changes to Flask libraries specific code were made, they were replaced with FastAPI equivalents. I've reduced the number of modules and put the endpoints logic in the main file, since the codebase for the initial app is minimal in size. Some new logic added since FastAPI modules behave slightly different, mainly around data received in requests sent.

How to review

Run it with Runner locally, ideally by pulling validator docker images and using make commands like make run-validator etc. using docker images and relevant branch of Runner.

Checklist

• eq-translations updated to support any new schema keys which need translation

[liamtoozer]

I think the run_app.sh might need to be updated with the new command as well?

[Yuyuutsu]

Works as expected through Runner.
This part of the Make Run Command does not work : poetry run ./scripts/run_app.sh.
Edit: Did not see liam already make a comment on this sorry!

[liamtoozer]

Great work! Tested locally