Fix/validation

[hellais]

Pydantic has an unusual default behaviour when you set a default value for Field:

validate_default	bool | None	If True, apply validation to the default value every time you create an instance. Otherwise, for performance reasons, the default value of the field is trusted and not validated.	

https://docs.pydantic.dev/latest/api/fields/

This was leading to a validation bypass when the fields that specified an invalid default value were not being set.

We fix that bug, but also add extra validation that checks if the author matches the email address and refactoring of the authentication logic.

[DecFox]

LGTM!