- Migrate 236+ class files from custodian_types to has_or_had_custodian_type
- Archive deprecated slots: custodian_type, custodian_types, custodian_type_broader/narrower/related
- Update main schema and manifest imports
- Fix Custodian.yaml class to use new slot
- Fix annotation format (list→scalar) in has_or_had_custodian_type.yaml
Rules applied:
- Rule 39: RiC-O naming convention (hasOrHad pattern)
- Rule 43: Slot nouns must be singular (multivalued:true for cardinality)
- Rule 38: Slot centralization with semantic URI
