feat: Add support for labels in automations (#11658)

- Add support for using labels as an action event for automation
 - Fix duplicated conversation_updated event dispatch for labels
 

Fixes https://github.com/chatwoot/chatwoot/issues/8539 and multiple
issues around duplication related to label change events.
---------

Co-authored-by: Muhsin Keloth <muhsinkeramam@gmail.com>

app/models/automation_rule.rb

@@ -36,7 +36,7 @@ class AutomationRule < ApplicationRecord
 
   def conditions_attributes
     %w[content email country_code status message_type browser_language assignee_id team_id referer city company inbox_id
-       mail_subject phone_number priority conversation_language]
+       mail_subject phone_number priority conversation_language labels]
   end
 
   def actions_attributes

app/models/concerns/labelable.rb

@@ -10,6 +10,8 @@ module Labelable
   end
 
   def add_labels(new_labels = nil)
+    return if new_labels.blank?
+
     new_labels = Array(new_labels) # Make sure new_labels is an array
     combined_labels = labels + new_labels
     update!(label_list: combined_labels)

app/models/conversation.rb

@@ -297,8 +297,6 @@ class Conversation < ApplicationRecord
     previous_labels, current_labels = previous_changes[:label_list]
     return unless (previous_labels.is_a? Array) && (current_labels.is_a? Array)
 
-    dispatcher_dispatch(CONVERSATION_UPDATED, previous_changes)
-
     create_label_added(user_name, current_labels - previous_labels)
     create_label_removed(user_name, previous_labels - current_labels)
   end