Accept string|array in retype_to_medical_webpage (Yoast wpseo_schema_webpage_type passes array on singular pages); normalize @type comparison; add regression test. QA: APPROVE — qa-reviews/peptide-repo-core/2026-06-13-077c4b0e518f682721abe6a115eac9bb2bf18186.md Agent-Session: jsonld-webpage-typefix v0.6.1 merge