Send Brrr push notifications for new webmentions

Dispatches a queued job to POST to a configured Brrr webhook whenever
a brand-new webmention is saved, so replies/likes/reposts show up as
push notifications instead of requiring a manual check of the site.

app/Jobs/ProcessWebMention.php

@@ -96,6 +96,7 @@ class ProcessWebMention implements ShouldQueue
         $webmention->type = $type;
         $webmention->mf2 = json_encode($microformats);
         $webmention->save();
+        dispatch(new NotifyBrrrOfWebMention($webmention));
     }
 
     /**