move autocomplete controllers

app/controllers/template_folders_autocomplete_controller.rb

@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+class TemplateFoldersAutocompleteController < ApplicationController
+  load_and_authorize_resource :template_folder, parent: false
+
+  LIMIT = 100
+
+  def index
+    template_folders = @template_folders.joins(:templates).where(templates: { archived_at: nil }).distinct
+    template_folders = TemplateFolders.search(template_folders, params[:q]).limit(LIMIT)
+
+    render json: template_folders.as_json(only: %i[name archived_at])
+  end
+end