Focused summary of a df_vpcstats() result: object dimensions, run-config
values (n_replicates, loq, strat_var), the column groups present
in stats, and a short head preview. Inspect the underlying data.frames
directly via x$stats and x$obs; inspect run config via x$config.
Usage
# S3 method for class 'vpc_stats'
print(x, n_head = 3, ...)