Fix #5360: Use OpenGraph's og:image metadata for posts.

* Add og:image:width, og:image:height, and og:image:type tags.
* Use og:video tags for videos.
* Use 720x720 instead of 150x150 preview images for videos.
* Add duration tag to JSON-LD data for videos.
* Add OpenGraph tags to media assets show page.
* Respect Twitter max image size limits.
* Don't include OpenGraph image tags when someone shares a plain https://danbooru.donmai.us link
  with no tag search. This caused random potentially NSFW images to be shown when someone shared a
  https://danbooru.donmai.us link on social media, which could be cached for long periods of time.

app/views/media_assets/show.html.erb

@@ -193,4 +193,8 @@
   </div>
 </div>
 
+<% content_for(:html_header) do %>
+  <%= render OpenGraphComponent.new(media_asset: @media_asset, current_user: CurrentUser.user) %>
+<% end %>
+
 <%= render "uploads/secondary_links" %>