feat(cloud): Add support for viewing status of SSL in custom domains (#12011)

# Pull Request Template

## Description

Fixes
[CW-4620](https://linear.app/chatwoot/issue/CW-4620/rethinking-custom-domains-in-chatwoot)

<img width="642" height="187" alt="Screenshot 2025-07-29 at 8 17 44 PM"
src="https://github.com/user-attachments/assets/ad2f5dac-4b27-4dce-93ca-6cbba74443fb"
/>


## Type of change

- [x] New feature (non-breaking change which adds functionality)

## How Has This Been Tested?



## Checklist:

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

---------

Co-authored-by: Vishnu Narayanan <iamwishnu@gmail.com>
Co-authored-by: Pranav <pranavrajs@gmail.com>
Co-authored-by: Pranav <pranav@chatwoot.com>

app/views/api/v1/accounts/portals/_portal.json.jbuilder

@@ -34,3 +34,10 @@ json.meta do
   json.categories_count portal.categories.try(:size)
   json.default_locale portal.default_locale
 end
+
+if portal.ssl_settings.present?
+  json.ssl_settings do
+    json.status portal.ssl_settings['cf_status']
+    json.verification_errors portal.ssl_settings['cf_verification_errors']
+  end
+end

app/views/mailers/portal_instructions_mailer/send_cname_instructions.liquid

@@ -0,0 +1,30 @@
+<tr>
+  <td>
+    <p>Hello there,</p>
+    <p>To complete the setup of your help center, you'll need to update the DNS settings for your custom domain: <strong>{{ cname_record | split: ' ' | first }}</strong>.</p>
+    <p>Please add the following CNAME record to your DNS provider's configuration:</p>
+  </td>
+</tr>
+
+<tr>
+  <td>
+    <p><strong>{{ cname_record }}</strong></p>
+  </td>
+</tr>
+
+<tr>
+  <td>
+    <p>Step-by-step Instructions:</p>
+
+    <ol>
+      <li>Log in to your DNS provider’s dashboard</li>
+      <li>Go to the DNS management section</li>
+      <li>Create a new CNAME record using the information above</li>
+      <li>Save the changes and allow up to 24 hours for the DNS to propagate</li>
+    </ol>
+
+    <p>Once the DNS record is live, your custom domain will automatically be secured with an SSL certificate.</p>
+
+    <p>If you have any questions or need help, feel free to reach out to our support team—we’re here to assist you.</p>
+  </td>
+</tr>