Migrate web app to FastAPI

[FKirton]

The existing web application uses Flask. The following benefits/improvements can be gained by migrating to FastAPI

• Integarion with Pydantic models

  • Defining data structures using Pydantic models allows data type checking and custom validation. FastAPI is fully integrated with Pydantic, which means that data validation can be removed from the web client and put where it belongs - with the data type declaration. This means that data will be validated whether the user interacts with the API programmatically, or via the web frontend (currently validation is happening in the web client only).

  Validation will be handled in issue #25.

• FastAPI provides Swagger API interactive documentation out of the box.

[FKirton]

Implemented