Add support for editing for published statuses (#16697)

* Add support for editing for published statuses

* Fix references to stripped-out code

* Various fixes and improvements

* Further fixes and improvements

* Fix updates being potentially sent to unauthorized recipients

* Various fixes and improvements

* Fix wrong words in test

* Fix notifying accounts that were tagged but were not in the audience

* Fix mistake

app/controllers/api/v1/statuses/sources_controller.rb

@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+class Api::V1::Statuses::SourcesController < Api::BaseController
+  include Authorization
+
+  before_action -> { doorkeeper_authorize! :read, :'read:statuses' }
+  before_action :set_status
+
+  def show
+    render json: @status, serializer: REST::StatusSourceSerializer
+  end
+
+  private
+
+  def set_status
+    @status = Status.find(params[:status_id])
+    authorize @status, :show?
+  rescue Mastodon::NotPermittedError
+    not_found
+  end
+end