Suite vocabulary constants

Import NS, LEGACY_NAMESPACES, canonicalize, isLegacy, and termsEqual from
@jeswr/suite-vocab. Writers use NS canonical bases. Readers compare classes with
termsEqual or canonicalize vocabulary predicates before typed access. Preserve resource
identifiers and literal contents. Type Index discovery must accept canonical and legacy
class IRIs; registration writes canonical classes. Do not put RDF builders, parsers or
migration I/O in this package. The federation ontology re-base is a separate task.