Returns the most recent season's START year – the seasons value
the nba_stats_* release loaders expect (see load_nba_stats_coaches()),
matching sdv-py's load_nba_stats_* Python loaders. It is defined as
most_recent_nba_season() - 1: most_recent_nba_season() returns the
current season's END year (hoopR's ESPN-family convention, used
directly – with no offset – by load_nba_*()), and the published
nba_stats_* assets are themselves keyed by that same END year, but the
nba_stats_* loaders take the season's START year and translate it
internally via seasons + 1. So this helper is not a plain alias of
most_recent_nba_season(); it is one less.