add models for Project, Task, Note, Category

app/models/phone_number.rb

@@ -0,0 +1,11 @@
+class PhoneNumber < ApplicationRecord
+  belongs_to :contact
+  enum :type, {
+    mobile: 0,
+    home: 1,
+    work: 2,
+    fax: 3,
+    other: 4
+  }, _prefix: true
+  validates :number, presence: true, format: { with: /\A\+?[0-9\s\-()]+\z/, message: "must be a valid phone number" }
+end