fix: Send raw content in webhook payloads instead of channel-rendered markdown (#13896)

Webhook payloads (`message_created`, `message_updated`) started sending
channel-rendered HTML in the `content` field instead of the original raw
message content after PR #12878. This broke downstream agent bots and
integrations that expected plain text or markdown. 
Closes https://linear.app/chatwoot/issue/PLA-109/webhook-payloads-send-channel-rendered-html-instead-of-raw-content

## How to reproduce

1. Connect an agent bot to a WebWidget inbox
2. Send a message with markdown formatting (e.g. `**bold**`) from the
widget
3. Observe the agent bot webhook payload — `content` field contains
`<p><strong>bold</strong></p>` instead of `**bold**`

## What changed

Split `MessageContentPresenter` into two public methods:
- `outgoing_content` — renders markdown for the target channel (used by
channel delivery services)
- `webhook_content` — returns raw content with CSAT survey URL when
applicable, no markdown rendering (used by `webhook_data`)

Updated `Message#webhook_data` to use `webhook_content` instead of
`outgoing_content`.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Co-authored-by: Sivin Varghese <64252451+iamsivin@users.noreply.github.com>

app/models/message.rb

@@ -176,7 +176,7 @@ class Message < ApplicationRecord
       additional_attributes: additional_attributes,
       content_attributes: content_attributes,
       content_type: content_type,
-      content: outgoing_content,
+      content: webhook_content,
       conversation: conversation.webhook_data,
       created_at: created_at,
       id: id,
@@ -195,6 +195,11 @@ class Message < ApplicationRecord
     MessageContentPresenter.new(self).outgoing_content
   end
 
+  # Raw content with survey URL (no markdown rendering) for webhook consumers
+  def webhook_content
+    MessageContentPresenter.new(self).webhook_content
+  end
+
   def email_notifiable_message?
     return false if private?
     return false if %w[outgoing template].exclude?(message_type)

app/presenters/message_content_presenter.rb

@@ -1,22 +1,28 @@
 class MessageContentPresenter < SimpleDelegator
   def outgoing_content
-    content_to_send = if should_append_survey_link?
-                        survey_link = survey_url(conversation.uuid)
-                        custom_message = inbox.csat_config&.dig('message')
-                        custom_message.present? ? "#{custom_message} #{survey_link}" : I18n.t('conversations.survey.response', link: survey_link)
-                      else
-                        content
-                      end
-
     Messages::MarkdownRendererService.new(
-      content_to_send,
+      content_with_survey_link,
       conversation.inbox.channel_type,
       conversation.inbox.channel
     ).render
   end
 
+  def webhook_content
+    content_with_survey_link
+  end
+
   private
 
+  def content_with_survey_link
+    if should_append_survey_link?
+      survey_link = survey_url(conversation.uuid)
+      custom_message = inbox.csat_config&.dig('message')
+      custom_message.present? ? "#{custom_message} #{survey_link}" : I18n.t('conversations.survey.response', link: survey_link)
+    else
+      content
+    end
+  end
+
   def should_append_survey_link?
     input_csat? && !inbox.web_widget?
   end

spec/models/message_spec.rb

@@ -401,12 +401,11 @@ RSpec.describe Message do
       expect(message.webhook_data.key?(:attachments)).to be false
     end
 
-    it 'uses outgoing_content for webhook content' do
-      message = create(:message, content: 'Test content')
-      expect(message).to receive(:outgoing_content).and_return('Outgoing test content')
+    it 'uses raw content without markdown rendering for webhook content' do
+      message = create(:message, content: 'Test **bold** content')
 
       webhook_data = message.webhook_data
-      expect(webhook_data[:content]).to eq('Outgoing test content')
+      expect(webhook_data[:content]).to eq('Test **bold** content')
     end
 
     it 'includes CSAT survey link in webhook content for input_csat messages' do
@@ -414,7 +413,6 @@ RSpec.describe Message do
       conversation = create(:conversation, inbox: inbox)
       message = create(:message, conversation: conversation, content_type: 'input_csat', content: 'Rate your experience')
 
-      expect(message.outgoing_content).to include('survey/responses/')
       expect(message.webhook_data[:content]).to include('survey/responses/')
     end
   end

spec/presenters/message_content_presenter_spec.rb

@@ -55,6 +55,34 @@ RSpec.describe MessageContentPresenter do
     end
   end
 
+  describe '#webhook_content' do
+    context 'when message is not input_csat' do
+      let(:content_type) { 'text' }
+      let(:content) { 'Regular **bold** message' }
+
+      it 'returns raw content without markdown rendering' do
+        expect(presenter.webhook_content).to eq('Regular **bold** message')
+      end
+    end
+
+    context 'when message is input_csat and inbox is not web widget' do
+      let(:content_type) { 'input_csat' }
+      let(:content) { 'Rate your experience' }
+
+      before do
+        allow(message.inbox).to receive(:web_widget?).and_return(false)
+      end
+
+      it 'includes CSAT survey URL without markdown rendering' do
+        with_modified_env 'FRONTEND_URL' => 'https://app.chatwoot.com' do
+          expected_url = "https://app.chatwoot.com/survey/responses/#{conversation.uuid}"
+          expect(presenter.webhook_content).to include(expected_url)
+          expect(presenter.webhook_content).not_to include('<p>')
+        end
+      end
+    end
+  end
+
   describe 'delegation' do
     let(:content_type) { 'text' }
     let(:content) { 'Test message' }