Introduce a separate controller for collection entropy config

which opens the door to rendering turbo frames in the responses to
collection edits.

app/controllers/collections/entropy_configurations_controller.rb

@@ -0,0 +1,14 @@
+class Collections::EntropyConfigurationsController < ApplicationController
+  include CollectionScoped
+
+  def update
+    @collection.entropy_configuration.update!(entropy_configuration_params)
+
+    redirect_to edit_collection_path(@collection), notice: "Collection updated"
+  end
+
+  private
+    def entropy_configuration_params
+      params.expect(collection: [ :auto_close_period, :auto_reconsider_period ])
+    end
+end

app/views/collections/edit/_auto_close.html.erb

@@ -1,4 +1,4 @@
 <div class="margin-block-end">
   <strong class="divider txt-large">Do or Die</strong>
-  <%= render "entropy/auto_close", model: collection %>
+  <%= render "entropy/auto_close", model: collection, url: collection_entropy_configuration_path(collection) %>
 </div>

config/routes.rb

@@ -18,6 +18,7 @@ Rails.application.routes.draw do
       resource :workflow, only: :update
       resource :involvement
       resource :publication
+      resource :entropy_configuration
     end
 
     resources :cards

test/controllers/collections/entropy_configurations_controller_test.rb

@@ -0,0 +1,17 @@
+require "test_helper"
+
+class Collections::EntropyConfigurationsControllerTest < ActionDispatch::IntegrationTest
+  setup do
+    sign_in_as :kevin
+    @collection = collections(:writebook)
+  end
+
+  test "update" do
+    put collection_entropy_configuration_path(@collection), params: { collection: { auto_close_period: 1.day, auto_reconsider_period: 2.days } }
+
+    assert_equal 1.day, @collection.entropy_configuration.reload.auto_close_period
+    assert_equal 2.days, @collection.entropy_configuration.reload.auto_reconsider_period
+
+    assert_redirected_to edit_collection_path(@collection)
+  end
+end