refactor: ニュース取得ロジックをモデルに移動

Author: nacchan99

app/controllers/home_controller.rb

@@ -3,6 +3,6 @@ def show
     @dojo_count = Dojo.active_dojos_count
     @regions_and_dojos = Dojo.group_by_region_on_active
     @prefectures_and_dojos = Dojo.group_by_prefecture_on_active
-    @news_items = News.all.order(published_at: :desc).limit(7)
+    @news_items = News.recent.limit(7)
   end
 end

app/models/news.rb

@@ -1,2 +1,3 @@
 class News < ApplicationRecord
+    scope :recent, -> { order(published_at: :desc) }
 end