add achievement management

db/migrate/20210814100232_create_wow_achievement_criteria.rb

@@ -0,0 +1,13 @@
+class CreateWowAchievementCriteria < ActiveRecord::Migration[6.1]
+  def change
+    create_table :wow_achievement_criteria do |t|
+      t.integer :criterium_id, null: false
+      t.jsonb :description
+      t.integer :amount
+
+      t.timestamps
+    end
+
+    add_index :wow_achievement_criteria, :criterium_id, unique: true
+  end
+end