A single facet value belonging to an Orkestra.ES.Facet.Attribute.
count is nil inside indexed documents (values carry no count when
stored) and only becomes a non_neg_integer() when the struct is produced
from an Elasticsearch aggregation result.
Summary
Types
@type t() :: %Orkestra.ES.Facet.Value{ code: String.t(), count: non_neg_integer() | nil, name: String.t() }
A facet value with an optional aggregation count.