Mastodon API: Add pleroma.unread_conversation_count to the Account entity

lib/pleroma/conversation/participation.ex

@@ -52,6 +52,15 @@ defmodule Pleroma.Conversation.Participation do
     participation
     |> read_cng(%{read: true})
     |> Repo.update()
+    |> case do
+      {:ok, participation} ->
+        participation = Repo.preload(participation, :user)
+        User.set_unread_conversation_count(participation.user)
+        {:ok, participation}
+
+      error ->
+        error
+    end
   end
 
   def mark_as_unread(participation) do
@@ -135,4 +144,12 @@ defmodule Pleroma.Conversation.Participation do
 
     {:ok, Repo.preload(participation, :recipients, force: true)}
   end
+
+  def unread_conversation_count_for_user(user) do
+    from(p in __MODULE__,
+      where: p.user_id == ^user.id,
+      where: not p.read,
+      select: %{count: count(p.id)}
+    )
+  end
 end