[fixes] Based on APM findings

app/controllers/api/v1/account_by_username_controller.rb

@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-class Api::V1::AccountByUsernameController < EmptyController
+class Api::V1::AccountByUsernameController < API::BaseController
   before_action :set_account
   before_action :check_account_suspension
   before_action :check_account_local

app/controllers/api/v1/timelines/home_controller.rb

@@ -62,6 +62,7 @@ class Api::V1::Timelines::HomeController < Api::BaseController
   end
 
   def regeneration_in_progress?
-    Redis.current.exists?("account:#{current_account.id}:regeneration")
+    false
+    # Redis.current.exists?("account:#{current_account.id}:regeneration")
   end
 end

app/controllers/settings/preferences_controller.rb

@@ -9,7 +9,7 @@ class Settings::PreferencesController < Settings::BaseController
 
   def update
     user_settings.update(user_settings_params.to_h)
-    current_user.force_regeneration!
+    # current_user.force_regeneration!
 
     if current_user.update(user_params)
       I18n.locale = current_user.locale