select area buffer based on cluster configuration
At the moment, buffered area is used for computation if present in table t_stratum, otherwise un-buffered area is used:
- https://gitlab.com/nfiesta/nfiesta_pg/-/blob/master/functions/extschema/fn_1p_data.sql#L160
- https://gitlab.com/nfiesta/nfiesta_pg/-/blob/master/functions/extschema/fn_2p_data.sql#L210.
It will be better to use parameter cluster_design present in table t_cluster_configuration for decision on what type of geometry area to use.