refactor otp

db/migrate/20260930061927_create_otp_challenges.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+class CreateOtpChallenges < ActiveRecord::Migration[8.1]
+  def change
+    create_table :otp_challenges do |t|
+      t.string :key, null: false
+      t.integer :version, null: false
+      t.string :nonce, null: false
+      t.integer :attempts, null: false, default: 0
+      t.datetime :expire_at, null: false
+      t.datetime :verified_at
+      t.datetime :created_at, null: false
+
+      t.index %i[key version], unique: true
+    end
+  end
+end