feat(seo): separate display headings and improve social metadata

www/src/layouts/PageLayout.astro

@@ -57,7 +57,7 @@ const heroImage = pageHeroImages[entry.data.slug];
 ---
 <BaseLayout title={entry.data.title} description={entry.data.description} image={entry.data.featuredImage || heroImage} lang={entry.data.lang}>
   {entry.data.slug === 'contact' && <Fragment slot="head"><link rel="stylesheet" href="https://unpkg.com/leaflet@1.9.4/dist/leaflet.css" integrity="sha256-p4NxAoJBhIIN+hmNHrzRCf9tD/miZyoHS5obTRR9BMY=" crossorigin="" /></Fragment>}
-  <PageHero title={bannerTitle} subtitle={entry.data.slug === 'faqs' ? 'FAQs' : undefined} image={heroImage} constrain />
+  <PageHero title={entry.data.displayH1 ?? bannerTitle} subtitle={entry.data.slug === 'faqs' ? 'FAQs' : undefined} image={heroImage} constrain />
   {entry.data.slug === 'team' && entry.data.lang === 'en'
     ? <TeamPage />
     : entry.data.slug === 'about' && entry.data.lang === 'en'