1 — Extract shared TypeScript types

Problem: OwlClass, ShaclConstraint, OwlShape, TaxonomyConcept, TaxonomyData are independently defined in OntologyBrowser.vue, YamlSchemas.vue, and RelationshipTypes.vue. Three copies of the same interfaces.

Action:

• Create .vitepress/data/types.ts with canonical type definitions
• Update all 3 components to import from there

Files touched:

• .vitepress/data/types.ts (new)
• .vitepress/theme/components/OntologyBrowser.vue
• .vitepress/theme/components/YamlSchemas.vue
• .vitepress/theme/components/RelationshipTypes.vue

Done when: No duplicate interface definitions. All components import from types.ts.