fix(websms): return subid from LabsMobile response in ApiSendSms

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

rest/controllers/websms_controller.go

@@ -196,7 +196,7 @@ func ApiSendSms(c *fiber.Ctx) error {
 	if err != nil {
 		return c.Status(500).JSON(fiber.Map{"error": errStr})
 	}
-	return c.JSON(fiber.Map{"ok": true, "id": resp.ID})
+	return c.JSON(fiber.Map{"ok": true, "id": resp.MsgID()})
 }
 
 func WebSmsIncomingWebhook(c *fiber.Ctx) error {