feat: Telegram Channel (#2901)

- Ability to configure telegram bots as a channel in chatwoot
- Receive a message sent to the telegram bot in chatwoot
- Ability to reply to telegram users from chatwoot
- Receive attachment messages in chatwoot

fixes: #1843

app/models/inbox.rb

@@ -78,6 +78,10 @@ class Inbox < ApplicationRecord
     channel_type == 'Channel::Api'
   end
 
+  def email?
+    channel_type == 'Channel::Email'
+  end
+
   def inbox_type
     channel.name
   end