feat: add support for fediverse:creator meta tag (#2593)

_config.yml

@@ -36,6 +36,7 @@ social:
   # It will be displayed as the default author of the posts and the copyright owner in the Footer
   name: your_full_name
   email: example@domain.com # change to your email address
+  fediverse_handle: "@you@domain.com" # change to your fediverse handle or leave empty
   links:
     # The first element serves as the copyright owner's link
     - https://twitter.com/username # change to your Twitter homepage

_includes/head.html

@@ -50,6 +50,11 @@
 
   {{ seo_tags }}
 
+  {%- if site.social.fediverse_handle %}
+    <!-- Fediverse handle/creator -->
+    <meta name="fediverse:creator" content="{{ site.social.fediverse_handle }}">
+  {% endif %}
+
   <title>
     {%- unless page.layout == 'home' -%}
       {{ page.title | append: ' | ' }}