Bulletins
Delete bulletin
Adds start_date/end_date/period query-param filtering to a viewset’s
list action, ranged against a single configurable date field.
Subclasses set date_range_field to the model field to filter on (e.g.
"created_at", "scheduled_at"). Call filter_by_date_range(queryset)
from get_queryset — filters apply only when at least one of the params
is present, so listings without them are unaffected.
For OpenAPI docs, extend the view’s parameters=[...] list with
DateRangeFilterMixin.schema_params().
