fix: Contacts page sort by created_at [CW-2262] (#7584)

Fixes the contacts page sort by created_at.
fixes: #7577

app/controllers/api/v1/accounts/contacts_controller.rb

@@ -4,6 +4,7 @@ class Api::V1::Accounts::ContactsController < Api::V1::Accounts::BaseController
   sort_on :name, internal_name: :order_on_name, type: :scope, scope_params: [:direction]
   sort_on :phone_number, type: :string
   sort_on :last_activity_at, internal_name: :order_on_last_activity_at, type: :scope, scope_params: [:direction]
+  sort_on :created_at, internal_name: :order_on_created_at, type: :scope, scope_params: [:direction]
   sort_on :company, internal_name: :order_on_company_name, type: :scope, scope_params: [:direction]
   sort_on :city, internal_name: :order_on_city, type: :scope, scope_params: [:direction]
   sort_on :country, internal_name: :order_on_country_name, type: :scope, scope_params: [:direction]

app/models/contact.rb

@@ -62,6 +62,14 @@ class Contact < ApplicationRecord
       )
     )
   }
+  scope :order_on_created_at, lambda { |direction|
+    order(
+      Arel::Nodes::SqlLiteral.new(
+        sanitize_sql_for_order("\"contacts\".\"created_at\" #{direction}
+          NULLS LAST")
+      )
+    )
+  }
   scope :order_on_company_name, lambda { |direction|
     order(
       Arel::Nodes::SqlLiteral.new(