check_reference_data() now returns the (possibly coerced) reference_data and
the call site captures the result so downstream code sees the fixed columns.
A new coerce_reference_data_columns() helper is called before the strict class
check inside check_reference_data(). It coerces columns to the expected types:
- mo -> as.mo() if not already <mo> class
- ab -> as.ab() if not already <ab> class
- character columns -> as.character() (e.g. host = NA becomes NA_character_)
- numeric columns -> as.double()
- logical columns -> as.logical()
This allows users to build a custom reference_data from a plain data.frame
without having to pre-apply as.mo()/as.ab() or worry about NA column types.
Updated the reference_data roxygen argument to document the auto-coercion and
restored the tests to the simpler form that uses plain character assignments,
relying on the new coercion instead of workarounds.
https://claude.ai/code/session_01Q8KtFFGG9qrjAgLJBbxG2U
ba09fba08b