Clean up and improve generated OpenGraph tags (#4901)

- Return all images as og:image
- Return videos as og:image (preview) and og:video
- Return profile:username on profiles

app/views/accounts/_og.html.haml

@@ -1,8 +1,9 @@
-%meta{ property: 'og:url', content: url }/
-%meta{ property: 'og:site_name', content: site_title }/
-%meta{ property: 'og:title', content: [yield(:page_title).strip.presence, site_title].compact.join(' - ') }/
-%meta{ property: 'og:description', content: account.note }/
-%meta{ property: 'og:image', content: full_asset_url(account.avatar.url(:original)) }/
-%meta{ property: 'og:image:width', content: '120' }/
-%meta{ property: 'og:image:height', content: '120' }/
-%meta{ property: 'twitter:card', content: 'summary' }/
+= opengraph 'og:url', url
+= opengraph 'og:site_name', site_title
+= opengraph 'og:title', [yield(:page_title).strip.presence, site_title].compact.join(' - ')
+= opengraph 'og:description', account.note
+= opengraph 'og:image', full_asset_url(account.avatar.url(:original))
+= opengraph 'og:image:width', '120'
+= opengraph 'og:image:height', '120'
+= opengraph 'twitter:card', 'summary'
+= opengraph 'profile:username', account.local_username_and_domain

app/views/accounts/show.html.haml

@@ -9,7 +9,7 @@
   %link{ rel: 'alternate', type: 'application/atom+xml', href: account_url(@account, format: 'atom') }/
   %link{ rel: 'alternate', type: 'application/activity+json', href: ActivityPub::TagManager.instance.uri_for(@account) }/
 
-  %meta{ property: 'og:type', content: 'profile' }/
+  = opengraph 'og:type', 'profile'
   = render 'og', account: @account, url: short_account_url(@account, only_path: false)
 
 - if show_landing_strip?