Add documentation for authors attribute in preview cards (#1512)

* Add documentation for `authors` attribute in preview cards

* Add `PreviewCardAuthor` entity

* Update PreviewCard.md

* Update PreviewCardAuthor.md

content/en/entities/PreviewCard.md

@@ -68,6 +68,7 @@ aliases: [
   "title": "‘I lost my £193,000 inheritance – with one wrong digit on my sort code’",
   "description": "When Peter Teich’s money went to another Barclays customer, the bank offered £25 as a token gesture",
   "type": "link",
+  "authors": [],
   "author_name": "",
   "author_url": "",
   "provider_name": "",
@@ -115,19 +116,28 @@ aliases: [
 **Version history:**\
 1.3.0 - added
 
+### `authors` {#authors}
+
+**Description:** Fediverse account of the authors of the original resource.\
+**Type:** Array of [PreviewCardAuthor]({{< relref "entities/PreviewCardAuthor">}})\
+**Version history:**\
+4.3.0 - added
+
 ### `author_name` {#author_name}
 
-**Description:** The author of the original resource.\
+**Description:** The author of the original resource. Deprecated since 4.3.0, clients should use `authors` instead.\
 **Type:** String\
 **Version history:**\
-1.3.0 - added
+1.3.0 - added\
+4.3.0 - deprecated
 
 ### `author_url` {#author_url}
 
-**Description:** A link to the author of the original resource.\
+**Description:** A link to the author of the original resource. Deprecated since 4.3.0, clients should use `authors` instead.\
 **Type:** String (URL)\
 **Version history:**\
-1.3.0 - added
+1.3.0 - added\
+4.3.0 - deprecated
 
 ### `provider_name` {#provider_name}
 

content/en/entities/PreviewCardAuthor.md

@@ -0,0 +1,39 @@
+---
+title: PreviewCardAuthor
+description: Represents an author in a rich preview card.
+menu:
+  docs:
+    parent: entities
+aliases: [
+  "/entities/PreviewCardAuthor",
+]
+---
+
+## Attributes
+
+### `name` {#name}
+
+**Description:** The original resource author's name. Replaces the deprecated `author_name` attribute of the preview card.\
+**Type:** String\
+**Version history:**\
+4.3.0 - added
+
+### `url` {#url}
+
+**Description:** A link to the author of the original resource. Replaces the deprecated `author_url` attribute of the preview card.\
+**Type:** String (URL)\
+**Version history:**\
+4.3.0 - added
+
+### `account` {{%nullable%}} {#account}
+
+**Description:** The fediverse account of the author.\
+**Type:** [Account]({{< relref "entities/Account">}})\
+**Version history:**\
+4.3.0 - added
+
+## See also
+
+{{< page-relref ref="entities/PreviewCard#authors" caption="PreviewCard (`authors` attribute)" >}}
+
+{{< caption-link url="https://github.com/mastodon/mastodon/blob/main/app/serializers/rest/preview_card_serializer.rb" caption="app/serializers/rest/preview_card_serializer.rb" >}}