fix: Add link to conversation in slack message (#6768)

lib/integrations/slack/send_on_slack_service.rb

@@ -37,18 +37,26 @@ class Integrations::Slack::SendOnSlackService < Base::SendOnChannelService
     if conversation.identifier.present?
       "#{private_indicator}#{message_text}"
     else
-      "#{formatted_inbox_name}#{email_subject_line}\n#{message_text}"
+      "#{formatted_inbox_name}#{formatted_conversation_link}#{email_subject_line}\n#{message_text}"
     end
   end
 
   def message_text
-    message.content.present? ? message.content.gsub(MENTION_REGEX, '\1') : message.content
+    if message.content.present?
+      message.content.gsub(MENTION_REGEX, '\1')
+    else
+      message.content
+    end
   end
 
   def formatted_inbox_name
     "\n*Inbox:* #{message.inbox.name} (#{message.inbox.inbox_type})\n"
   end
 
+  def formatted_conversation_link
+    "*Conversation:* #{link_to_conversation}\n"
+  end
+
   def email_subject_line
     return '' unless message.inbox.email?
 
@@ -127,4 +135,8 @@ class Integrations::Slack::SendOnSlackService < Base::SendOnChannelService
   def slack_client
     @slack_client ||= Slack::Web::Client.new(token: hook.access_token)
   end
+
+  def link_to_conversation
+    "#{ENV.fetch('FRONTEND_URL', nil)}/app/accounts/#{conversation.account_id}/conversations/#{conversation.display_id}"
+  end
 end