Refactor TextField to properly apply input props and types

closes https://gitlab.developers.cam.ac.uk/uis/devops/digital-admissions/admissions-portal/ap-frontend/-/issues/133 in admissions portal

Somewhere in the process of adding features to the TextField the name prop was removed, which we use widely to extract values from the input when using uncontrolled form submissions. In the process of adding it back in it became clear the types had grown out of control. Hopefully these types are much easier to read, understand and maintain.