feat: Add twilio content templates (#12277)

Implements comprehensive Twilio WhatsApp content template support (Phase
1) enabling text, media, and quick reply templates with proper parameter
conversion, sync capabilities, and feature flag protection.

###  Features Implemented

  **Template Types Supported**

  - Basic Text Templates: Simple text with variables ({{1}}, {{2}})
  - Media Templates: Image/Video/Document templates with text variables
  - Quick Reply Templates: Interactive button templates
- Phase 2 (Future): List Picker, Call-to-Action, Catalog, Carousel,
Authentication templates

  **Template Synchronization**

- API Endpoint: POST
/api/v1/accounts/{account_id}/inboxes/{inbox_id}/sync_templates
  - Background Job: Channels::Twilio::TemplatesSyncJob
  - Storage: JSONB format in channel_twilio_sms.content_templates
  - Auto-categorization: UTILITY, MARKETING, AUTHENTICATION categories

 ###  Template Examples Tested


  #### Text template
```
  { "name": "greet", "language": "en" }
```
  #### Template with variables
```
  { "name": "order_status", "parameters": [{"type": "body", "parameters": [{"text": "John"}]}] }
```

  #### Media template with image
```
  { "name": "product_showcase", "parameters": [
    {"type": "header", "parameters": [{"image": {"link": "image.jpg"}}]},
    {"type": "body", "parameters": [{"text": "iPhone"}, {"text": "$999"}]}
  ]}
```
#### Preview

<img width="1362" height="1058" alt="CleanShot 2025-08-26 at 10 01
51@2x"
src="https://github.com/user-attachments/assets/cb280cea-08c3-44ca-8025-58a96cb3a451"
/>

<img width="1308" height="1246" alt="CleanShot 2025-08-26 at 10 02
02@2x"
src="https://github.com/user-attachments/assets/9ea8537a-61e9-40f5-844f-eaad337e1ddd"
/>

#### User guide

https://www.chatwoot.com/hc/user-guide/articles/1756195741-twilio-content-templates

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Sivin Varghese <64252451+iamsivin@users.noreply.github.com>

app/javascript/dashboard/components-next/NewConversation/components/ComposeNewConversationForm.vue

@@ -74,6 +74,9 @@ const inboxTypes = computed(() => ({
   isTwilioSMS:
     props.targetInbox?.channelType === INBOX_TYPES.TWILIO &&
     props.targetInbox?.medium === 'sms',
+  isTwilioWhatsapp:
+    props.targetInbox?.channelType === INBOX_TYPES.TWILIO &&
+    props.targetInbox?.medium === 'whatsapp',
 }));
 
 const whatsappMessageTemplates = computed(() =>
@@ -261,6 +264,28 @@ const handleSendWhatsappMessage = async ({ message, templateParams }) => {
     isFromWhatsApp: true,
   });
 };
+
+const handleSendTwilioMessage = async ({ message, templateParams }) => {
+  const twilioMessagePayload = prepareWhatsAppMessagePayload({
+    targetInbox: props.targetInbox,
+    selectedContact: props.selectedContact,
+    message,
+    templateParams,
+    currentUser: props.currentUser,
+  });
+  await emit('createConversation', {
+    payload: twilioMessagePayload,
+    isFromWhatsApp: true,
+  });
+};
+
+const shouldShowMessageEditor = computed(() => {
+  return (
+    !inboxTypes.value.isWhatsapp &&
+    !showNoInboxAlert.value &&
+    !inboxTypes.value.isTwilioWhatsapp
+  );
+});
 </script>
 
 <template>
@@ -311,7 +336,7 @@ const handleSendWhatsappMessage = async ({ message, templateParams }) => {
     />
 
     <MessageEditor
-      v-if="!inboxTypes.isWhatsapp && !showNoInboxAlert"
+      v-if="shouldShowMessageEditor"
       v-model="state.message"
       :message-signature="messageSignature"
       :send-with-signature="sendWithSignature"
@@ -331,6 +356,7 @@ const handleSendWhatsappMessage = async ({ message, templateParams }) => {
       :is-whatsapp-inbox="inboxTypes.isWhatsapp"
       :is-email-or-web-widget-inbox="inboxTypes.isEmailOrWebWidget"
       :is-twilio-sms-inbox="inboxTypes.isTwilioSMS"
+      :is-twilio-whats-app-inbox="inboxTypes.isTwilioWhatsapp"
       :message-templates="whatsappMessageTemplates"
       :channel-type="inboxChannelType"
       :is-loading="isCreating"
@@ -347,6 +373,7 @@ const handleSendWhatsappMessage = async ({ message, templateParams }) => {
       @discard="$emit('discard')"
       @send-message="handleSendMessage"
       @send-whatsapp-message="handleSendWhatsappMessage"
+      @send-twilio-message="handleSendTwilioMessage"
     />
   </div>
 </template>