`datetime` fields are indexed as `TAG`, sortable queries fail silently

[elicore]

redis-om-python: 0.1.2
python: 3.10

When setting a datetime Field with index=True, the field index is created as a TAG. Queries that use > or < return no data, as the query expression is evaluated to "".

This happens in both HashModel and JsonModel.

If the field is also defined with sortable=True AND the model is a JsonModel, the model definition raises a RedisModelError:

In this Preview release, TAG fields cannot be marked as sortable. Problem field: end_date. See docs: TODO

However if the model is a HashModel, no such exception is raised.

Possible solutions:

• Store and index datetime fields as NUMERIC.
• Index daetime fields as TEXT and apply parsetime to create a new query field for sorting.

[XChikuX]

Happens with a regular string field as well.

class RedisUser(JsonModel):
    """
    RedisUser class: A class that defines the RedisUser model
    """

    fname: str = Field(
        index=True,
        sortable=True,
        title="First Name",
        min_length=2,
        max_length=30,
        description="Enter your first name.",
    )

I get aredis_om.model.model.RedisModelError: In this Preview release, TAG fields cannot be marked as sortable. Problem field: fname. See docs: TODO