feat(Breadcrumb): handle labelClass and merge iconClass

src/runtime/types/breadcrumb.d.ts

@@ -2,6 +2,7 @@ import type { Link } from './link'
 
 export interface BreadcrumbLink extends Link {
   label: string
+  labelClass?: string
   icon?: string
   iconClass?: string
   // FIXME: This is a workaround for `link.to` not being resolved although it extends `NuxtLinkProps`