chore: Generate webhook-verify-token automatically (#5593)

- Autogenerate webhook verification token in the WhatsAppCloud channel.

Co-authored-by: Sojan <sojan@pepalo.com>

app/models/channel/whatsapp.rb

@@ -25,11 +25,12 @@ class Channel::Whatsapp < ApplicationRecord
 
   # default at the moment is 360dialog lets change later.
   PROVIDERS = %w[default whatsapp_cloud].freeze
+  before_validation :ensure_webhook_verify_token
 
   validates :provider, inclusion: { in: PROVIDERS }
-
   validates :phone_number, presence: true, uniqueness: true
   validate :validate_provider_config
+
   after_create :sync_templates
 
   def name
@@ -56,6 +57,10 @@ class Channel::Whatsapp < ApplicationRecord
 
   private
 
+  def ensure_webhook_verify_token
+    provider_config['webhook_verify_token'] ||= SecureRandom.hex(16) if provider == 'whatsapp_cloud'
+  end
+
   def validate_provider_config
     errors.add(:provider_config, 'Invalid Credentials') unless provider_service.validate_provider_config?
   end