設定画面 (#34) (#397)

Reviewed-on: #397
Co-authored-by: miteruzo <miteruzo@naver.com>
Co-committed-by: miteruzo <miteruzo@naver.com>

backend/app/models/user.rb

@@ -7,7 +7,8 @@ class User < ApplicationRecord
 
   has_many :created_posts,
            class_name: 'Post', foreign_key: :uploaded_user_id, dependent: :nullify
-  has_many :settings
+  has_one :setting, dependent: :destroy
+  has_many :theme_slots, class_name: 'UserThemeSlot', dependent: :destroy
   has_many :user_ips, dependent: :destroy
   has_many :ip_addresses, through: :user_ips
   has_many :user_post_views, dependent: :destroy