feat: Add manual WhatsApp templates sync with UI (#12007)

Fixes https://github.com/chatwoot/chatwoot/issues/9600

**Summary**
- Added manual WhatsApp templates sync functionality accessible via UI
- Added refresh button in both inbox settings and template picker modal
- Enhanced template picker to always show for WhatsApp Cloud channels
(even when empty)


**Preview**

<img width="1456" height="798" alt="CleanShot 2025-07-22 at 14 15 28@2x"
src="https://github.com/user-attachments/assets/8a04ff26-61fa-42ee-a1b8-5e06433ae6e0"
/>


<img width="2376" height="1574" alt="CleanShot 2025-07-22 at 14 19
24@2x"
src="https://github.com/user-attachments/assets/1c772034-04ff-484d-88dd-ca8123e93065"
/>

---------

Co-authored-by: iamsivin <iamsivin@gmail.com>

app/javascript/dashboard/i18n/locale/en/inboxMgmt.json

@@ -600,6 +600,10 @@
       "WHATSAPP_SECTION_UPDATE_BUTTON": "Update",
       "WHATSAPP_WEBHOOK_TITLE": "Webhook Verification Token",
       "WHATSAPP_WEBHOOK_SUBHEADER": "This token is used to verify the authenticity of the webhook endpoint.",
+      "WHATSAPP_TEMPLATES_SYNC_TITLE": "Sync Templates",
+      "WHATSAPP_TEMPLATES_SYNC_SUBHEADER": "Manually sync message templates from WhatsApp to update your available templates.",
+      "WHATSAPP_TEMPLATES_SYNC_BUTTON": "Sync Templates",
+      "WHATSAPP_TEMPLATES_SYNC_SUCCESS": "Templates sync initiated successfully. It may take a couple of minutes to update.",
       "UPDATE_PRE_CHAT_FORM_SETTINGS": "Update Pre Chat Form Settings"
     },
     "HELP_CENTER": {

app/javascript/dashboard/i18n/locale/en/whatsappTemplates.json

@@ -8,6 +8,10 @@
         "PICKER": {
             "SEARCH_PLACEHOLDER": "Search Templates",
             "NO_TEMPLATES_FOUND": "No templates found for",
+            "NO_TEMPLATES_AVAILABLE": "No WhatsApp templates available. Click refresh to sync templates from WhatsApp.",
+            "REFRESH_BUTTON": "Refresh templates",
+            "REFRESH_SUCCESS": "Templates refresh initiated. It may take a couple of minutes to update.",
+            "REFRESH_ERROR": "Failed to refresh templates. Please try again.",
             "LABELS": {
                 "LANGUAGE": "Language",
                 "TEMPLATE_BODY": "Template Body",