fix: always include item field in BreadcrumbList JSON-LD

Fixes Google Search Console error: missing field "item" in itemListElement.
Also removes unused ahrefs site verification meta tag.

site/src/components/Breadcrumbs.astro

@@ -15,6 +15,8 @@ const { items, base } = Astro.props;
 
 const allItems = [{ label: 'Home', href: `${base}/` }, ...items];
 
+const currentUrl = Astro.url.href;
+
 const jsonLd = {
   '@context': 'https://schema.org',
   '@type': 'BreadcrumbList',
@@ -22,7 +24,7 @@ const jsonLd = {
     '@type': 'ListItem',
     position: i + 1,
     name: item.label,
-    ...(item.href ? { item: `${SITE_ORIGIN}${item.href}` } : {}),
+    item: item.href ? `${SITE_ORIGIN}${item.href}` : currentUrl,
   })),
 };
 ---

site/src/layouts/BaseLayout.astro

@@ -44,7 +44,6 @@ const canonical = canonicalUrl ?? `${SITE_ORIGIN}${base}${Astro.url.pathname.rep
   <meta name="viewport" content="width=device-width, initial-scale=1" />
   <meta name="theme-color" content="#E6522C" />
   <meta name="author" content={AUTHOR_NAME} />
-  <meta name="ahrefs-site-verification" content="da5bb74a487d1869ab3a7854e35e12f247bad1cb52116ede21ad9d01e26d1c68">
   {noIndex && <meta name="robots" content="noindex" />}
 
   <SEO