Re-create dbt artifact Pydantic classes from official jsonschema

[atvaccaro]

We should use https://docs.pydantic.dev/latest/datamodel_code_generator combined with schemas.getdbt.com to produce generated classes that we can inherit, or just use as fixed types and write more function-oriented code. This will be easier to update/maintain than custom classes.

This was done in #2545 but we hit an issue with dbt 1.5 so we reverted.

I need to change the dbt test fingerprints to use the string value of the status enum. Otherwise, the fingerprint will change if the type of the enum differs.

We should merge/resolve issues as necessary after this is done.