[Code health] Consistent naming of local DB converters

Pretty much every local db entity has to/from conversion methods for converting a corresponding model object to the local db entity type. However, we don't name these consistently. Sometimes they are named `toModel`, sometimes `toObject` sometimes `to`...

We should pick a consistent naming scheme. For extra clarity, my vote goes toward `toModel`; e.g.

`toLocationOfInterestModel`; `fromLocationOfInterestModel`; `toAuditInfoModel`; `fromAuditInfoModel`