Calls every morie_otis_* churn callable on its respective
input data.frame and returns a named list of results. Each
input is independent: pass NULL (or omit) to skip a metric.
If out_dir is supplied, each result is also serialised to
disk.
Usage
morie_otis_churn_analyze_all(
b01 = NULL,
b02 = NULL,
b09 = NULL,
a01 = NULL,
out_dir = NULL
)