Create paginable/research_outputs_controller.rb

This commit, along with e289fba are being made to resolve #935.

app/controllers/paginable/research_outputs_controller.rb

@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+module Paginable
+  # Controller for paginating/sorting/searching the research_outputs table
+  class ResearchOutputsController < ApplicationController
+    include Paginable
+
+    after_action :verify_authorized
+
+    # GET /paginable/plans/:plan_id/research_outputs
+    def index
+      @plan = Plan.find_by(id: params[:plan_id])
+
+      # Same @research_outputs assignment as app/controllers/research_outputs_controller.rb
+      @research_outputs = ResearchOutput.includes(:repositories).where(plan_id: @plan.id)
+      # Same authorize handling as app/controllers/research_outputs_controller.rb
+      authorize @research_outputs.first || ResearchOutput.new(plan_id: @plan.id)
+      paginable_renderise(
+        partial: 'index',
+        scope: @research_outputs,
+        query_params: { sort_field: 'research_outputs.title' },
+        format: :json
+      )
+    end
+  end
+end