Refactor media upload

Use Upload Media logic from Pleroma

Backend changes for picture upload

Move AS <-> Model conversion to separate module

Front changes

Downgrade apollo-client: https://github.com/Akryum/vue-apollo/issues/577

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/service/activity_pub/converter.ex

@@ -0,0 +1,9 @@
+defmodule Mobilizon.Service.ActivityPub.Converter do
+  @moduledoc """
+  Converter behaviour
+
+  This module allows to convert from ActivityStream format to our own internal one, and back
+  """
+  @callback as_to_model_data(map()) :: map()
+  @callback model_to_as(struct()) :: map()
+end