Read default stakeholder groups
sdm_read_groups.RdFetches the standard stakeholder groups from the SDM API and
returns them as ready-to-use sdm_group objects. Pass species
to get species-specific defaults instead of generic ones.
Value
A list of sdm_group objects. Each group has fields:
id, name, description, and weights (named numeric
vector keyed by objective id (e.g., obj_1), summing to 1.0).
Pass these directly to sdm_scenario().