schema
Whether a schema catalog is created, collected into and read from.
false costs nothing: no observer, no .cat sidecar written on any flush or compaction, and no fold on any query. It is a construction-time choice rather than a runtime branch precisely so that a store which wants neither layer pays for neither.
With this off, Rabosh.schema and Rabosh.indexCandidates throw rather than returning an empty model — a model of nothing and a model that was never collected are different answers.