chore: consider X-original-sender to create contact in case of group mail (#2841)

For emails forwarded from google groups, Google rewrites the FROM address to the group email and the original email will be available under X-Original-Sender. This PR enables chatwoot to handle this case.

Fixes: #2715

app/mailboxes/support_mailbox.rb

@@ -58,7 +58,7 @@ class SupportMailbox < ApplicationMailbox
   end
 
   def find_or_create_contact
-    @contact = @inbox.contacts.find_by(email: processed_mail.from.first)
+    @contact = @inbox.contacts.find_by(email: @processed_mail.original_sender)
     if @contact.present?
       @contact_inbox = ContactInbox.find_by(inbox: @inbox, contact: @contact)
     else
@@ -72,7 +72,7 @@ class SupportMailbox < ApplicationMailbox
       inbox: @inbox,
       contact_attributes: {
         name: identify_contact_name,
-        email: processed_mail.from.first,
+        email: @processed_mail.original_sender,
         additional_attributes: {
           source_id: "email:#{processed_mail.message_id}"
         }

app/presenters/mail_presenter.rb

@@ -82,6 +82,10 @@ class MailPresenter < SimpleDelegator
     @mail.from.map(&:downcase)
   end
 
+  def original_sender
+    @mail['X-Original-Sender'].try(:value) || from.first
+  end
+
   private
 
   # forcing the encoding of the content to UTF-8 so as to be compatible with database and serializers