Move Curated pool updater to Danbooru.

* Move the Curated pool updater from Reportbooru to Danbooru.

* Change the process for selecting curated posts. Previously it was
  every post from the last week with at least three supervotes. This was
  flawed because it included both super-upvotes and super-downvotes. Now
  it's the top 100 posts from the last week, ordered from most super-upvoted
  to least.

app/logical/curated_pool_updater.rb

@@ -0,0 +1,16 @@
+module CuratedPoolUpdater
+  def self.curated_posts(date_range: (1.week.ago..Time.now), limit: 100)
+    posts = Post.where(created_at: date_range)
+    posts = posts.joins(:votes).where("post_votes.score": SuperVoter::MAGNITUDE)
+    posts = Post.where(id: posts.group(:id).order(Arel.sql("COUNT(*) DESC")).limit(limit))
+    posts
+  end
+
+  def self.update_pool!(pool_id = Danbooru.config.curated_pool_id)
+    return unless pool_id.present?
+
+    CurrentUser.scoped(User.system, "127.0.0.1") do
+      Pool.find(pool_id).update!(post_ids: curated_posts.pluck(:id))
+    end
+  end
+end

app/logical/danbooru_maintenance.rb

@@ -21,6 +21,7 @@ module DanbooruMaintenance
     TagChangeRequestPruner.warn_all
     TagChangeRequestPruner.reject_all
     Ban.prune!
+    CuratedPoolUpdater.update_pool!
 
     ActiveRecord::Base.connection.execute("vacuum analyze") unless Rails.env.test?
   rescue Exception => exception