add folders migration

app/models/template_folder.rb

@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+# == Schema Information
+#
+# Table name: template_folders
+#
+#  id         :bigint           not null, primary key
+#  deleted_at :datetime
+#  name       :string           not null
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#  account_id :bigint           not null
+#  author_id  :bigint           not null
+#
+# Indexes
+#
+#  index_template_folders_on_account_id  (account_id)
+#  index_template_folders_on_author_id   (author_id)
+#
+# Foreign Keys
+#
+#  fk_rails_...  (account_id => accounts.id)
+#  fk_rails_...  (author_id => users.id)
+#
+class TemplateFolder < ApplicationRecord
+  DEFAULT_NAME = 'Default'
+
+  belongs_to :author, class_name: 'User'
+  belongs_to :account
+
+  has_many :templates, dependent: :destroy
+
+  scope :active, -> { where(deleted_at: nil) }
+end