fix: map smtp_use_tls/ssl from API response in loadEmailSettings

The previous fix added the fields to the API response but missed mapping
them in loadEmailSettings() where the response is stored into
emailSettings. The values were dropped before reaching populateEmailForm.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/modules/core/static/admin/js/settings.js

@@ -329,6 +329,8 @@ function adminSettings() {
                     smtp_host: data.smtp_host || '',
                     smtp_port: data.smtp_port || 587,
                     smtp_user: data.smtp_user || '',
+                    smtp_use_tls: data.smtp_use_tls ?? true,
+                    smtp_use_ssl: data.smtp_use_ssl ?? false,
                     mailgun_domain: data.mailgun_domain || '',
                     aws_region: data.aws_region || '',
                     debug: data.debug || false,