fix: setup webhook for create and update should be done after db commit (#12176)

## Reference
https://github.com/chatwoot/chatwoot/pull/12149#issuecomment-3178108388

## Description

setup_webhook was done before the save, and hence the meta webhook
validation might fail because of a race condition where the facebook
validation is done before we saving the entry to the database.

## Type of change

Please delete options that are not relevant.

- [ ] Bug fix (non-breaking change which fixes an issue)

## How Has This Been Tested?

- New inbox creation, webhook validation
- Existing inbox update, webhook validation
- 
<img width="614" height="674" alt="image"
src="https://github.com/user-attachments/assets/be223945-deed-475a-82e5-3ae9c54a13fa"
/>


## Checklist:

- [ ] My code follows the style guidelines of this project
- [ ] I have performed a self-review of my code
- [ ] I have commented on my code, particularly in hard-to-understand
areas
- [ ] I have made corresponding changes to the documentation
- [ ] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] New and existing unit tests pass locally with my changes
- [ ] Any dependent changes have been merged and published in downstream
modules

---------

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

app/models/channel/whatsapp.rb

@@ -32,7 +32,6 @@ class Channel::Whatsapp < ApplicationRecord
   validates :phone_number, presence: true, uniqueness: true
   validate :validate_provider_config
 
-  before_save :setup_webhooks
   after_create :sync_templates
   before_destroy :teardown_webhooks
 
@@ -60,6 +59,13 @@ class Channel::Whatsapp < ApplicationRecord
   delegate :media_url, to: :provider_service
   delegate :api_headers, to: :provider_service
 
+  def setup_webhooks
+    perform_webhook_setup
+  rescue StandardError => e
+    Rails.logger.error "[WHATSAPP] Webhook setup failed: #{e.message}"
+    prompt_reauthorization!
+  end
+
   private
 
   def ensure_webhook_verify_token
@@ -70,34 +76,6 @@ class Channel::Whatsapp < ApplicationRecord
     errors.add(:provider_config, 'Invalid Credentials') unless provider_service.validate_provider_config?
   end
 
-  def setup_webhooks
-    return unless should_setup_webhooks?
-
-    perform_webhook_setup
-  rescue StandardError => e
-    handle_webhook_setup_error(e)
-  end
-
-  def provider_config_changed?
-    will_save_change_to_provider_config?
-  end
-
-  def should_setup_webhooks?
-    whatsapp_cloud_provider? && embedded_signup_source? && webhook_config_present? && provider_config_changed?
-  end
-
-  def whatsapp_cloud_provider?
-    provider == 'whatsapp_cloud'
-  end
-
-  def embedded_signup_source?
-    provider_config['source'] == 'embedded_signup'
-  end
-
-  def webhook_config_present?
-    provider_config['business_account_id'].present? && provider_config['api_key'].present?
-  end
-
   def perform_webhook_setup
     business_account_id = provider_config['business_account_id']
     api_key = provider_config['api_key']
@@ -105,12 +83,6 @@ class Channel::Whatsapp < ApplicationRecord
     Whatsapp::WebhookSetupService.new(self, business_account_id, api_key).perform
   end
 
-  def handle_webhook_setup_error(error)
-    Rails.logger.error "[WHATSAPP] Webhook setup failed: #{error.message}"
-    # Don't raise the error to prevent channel creation from failing
-    # Webhooks can be retried later
-  end
-
   def teardown_webhooks
     Whatsapp::WebhookTeardownService.new(self).perform
   end