WhatsApp API returns "(#100) Invalid parameter — Parameter name is missing or empty" for templates that use named variables. - chat.php sendTemplate(): collect params as [{name, value}] objects using data-var-index as the parameter name - WhatsAppService::sendTemplateMessage(): handle {name, value} objects in the indexed-array path by emitting {type, parameter_name, text} (backward-compatible — plain strings still work as positional params) Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>