Add service for creating invites

app/services/create_invitations.rb

@@ -0,0 +1,17 @@
+class CreateInvitations < ApplicationService
+  def initialize(user:, amount:, notify: true)
+    @user = user
+    @amount = amount
+    @notify = notify
+  end
+
+  def call
+    @amount.times do
+      Invitation.create(user: @user)
+    end
+
+    if @notify
+      NotificationMailer.with(user: @user).new_invitations_available.deliver_later
+    end
+  end
+end