## Bug description

When calculating Trends results with an aggregated (e.g. single output, like big number) display type, WAU/MAU don't work. This is because we have an `ACTIVE_USERS_SQL` query for time series display types, but we don't have a version of this for aggregated display types. (See ZEN-1043.)

## How to reproduce

1. Create an insight with a single WAU or MAU series.
2. Switch display type to "Number".
3. Open the "Debug ClickHouse queries" modal from the command palette.
4. See `COUNT(*)` instead of `COUNT(DISTINCT person_id)`.

#### *Thank you* for your bug report – we love squashing them!

posthog/queries/breakdown_props.py
parsed_date_from=parsed_date_from,
            parsed_date_to=parsed_date_to,
            prop_filters=prop_filters,
            aggregate_operation=aggregate_operation,
            person_join_clauses=person_join_clauses,
            groups_join_clauses=groups_join_clause,
            sessions_join_clauses=sessions_join_clause,
            null_person_filter=null_person_filter,
            **entity_format_params,
        )
    return insight_sync_execute(
        elements_query,
        {
            "key": filter.breakdown,
            "limit": filter.breakdown_limit_or_default,
            "team_id": team.pk,
            "offset": filter.offset,
            "timezone": team.timezone,
            **prop_filter_params,
            **entity_params,
            **person_join_params,
            **groups_join_params,
            **sessions_join_params,
            **extra_params,
            **date_params,
        },
        query_type="get_breakdown_prop_values",
        filter=filter,
    )[0][0]
def _to_value_expression(