Include preview cards in status entity in REST API (#9120)

* Include preview cards in status entity in REST API

* Display preview card in-stream

* Improve in-stream display of preview cards

app/models/status.rb

@@ -89,6 +89,7 @@ class Status < ApplicationRecord
                    :conversation,
                    :status_stat,
                    :tags,
+                   :preview_cards,
                    :stream_entry,
                    active_mentions: :account,
                    reblog: [
@@ -96,6 +97,7 @@ class Status < ApplicationRecord
                      :application,
                      :stream_entry,
                      :tags,
+                     :preview_cards,
                      :media_attachments,
                      :conversation,
                      :status_stat,
@@ -163,6 +165,10 @@ class Status < ApplicationRecord
     reblog
   end
 
+  def preview_card
+    preview_cards.first
+  end
+
   def title
     if destroyed?
       "#{account.acct} deleted status"