Add profile directory (#9427)

Fix #5578

app/models/account_stat.rb

@@ -1,5 +1,4 @@
 # frozen_string_literal: true
-
 # == Schema Information
 #
 # Table name: account_stats
@@ -11,16 +10,25 @@
 #  followers_count :bigint(8)        default(0), not null
 #  created_at      :datetime         not null
 #  updated_at      :datetime         not null
+#  last_status_at  :datetime
 #
 
 class AccountStat < ApplicationRecord
   belongs_to :account, inverse_of: :account_stat
 
   def increment_count!(key)
-    update(key => public_send(key) + 1)
+    update(attributes_for_increment(key))
   end
 
   def decrement_count!(key)
     update(key => [public_send(key) - 1, 0].max)
   end
+
+  private
+
+  def attributes_for_increment(key)
+    attrs = { key => public_send(key) + 1 }
+    attrs[:last_status_at] = Time.now.utc if key == :statuses_count
+    attrs
+  end
 end