Address liking / announcing to the original author.

lib/pleroma/web/activity_pub/activity_pub.ex

@@ -33,7 +33,7 @@ def like(%User{ap_id: ap_id} = user, %Object{data: %{ "id" => id}} = object) do
           "type" => "Like",
           "actor" => ap_id,
           "object" => id,
-          "to" => [User.ap_followers(user)]
+          "to" => [User.ap_followers(user), object.data["actor"]]
         }
 
         {:ok, activity} = insert(data)
@@ -142,7 +142,7 @@ def announce(%User{ap_id: ap_id} = user, %Object{data: %{"id" => id}} = object)
       "type" => "Announce",
       "actor" => ap_id,
       "object" => id,
-      "to" => [User.ap_followers(user)]
+      "to" => [User.ap_followers(user), object.data["actor"]]
     }
 
     {:ok, activity} = insert(data)

test/web/activity_pub/activity_pub_test.exs

@@ -124,7 +124,7 @@ test "adds a like activity to the db" do
       assert like_activity.data["actor"] == user.ap_id
       assert like_activity.data["type"] == "Like"
       assert like_activity.data["object"] == object.data["id"]
-      assert like_activity.data["to"] == [User.ap_followers(user)]
+      assert like_activity.data["to"] == [User.ap_followers(user), note_activity.data["actor"]]
       assert object.data["like_count"] == 1
       assert object.data["likes"] == [user.ap_id]
 
@@ -171,7 +171,7 @@ test "adds an announce activity to the db" do
       {:ok, announce_activity, object} = ActivityPub.announce(user, object)
       assert object.data["announcement_count"] == 1
       assert object.data["announcements"] == [user.ap_id]
-      assert announce_activity.data["to"] == [User.ap_followers(user)]
+      assert announce_activity.data["to"] == [User.ap_followers(user), note_activity.data["actor"]]
       assert announce_activity.data["object"] == object.data["id"]
       assert announce_activity.data["actor"] == user.ap_id
     end