feat: add paid author and conference hosting with Stripe

public/script/forms.js

@@ -92,7 +92,7 @@ export function submitForm(event, callback) {
     if (el._field) validate(el);
   });
   if (form && !form.checkValidity()) {
-    const invalid = form.querySelector(":invalid");
+    const invalid = form.querySelector("input:invalid, select:invalid, textarea:invalid");
     invalid?.scrollIntoView?.({ block: "center" });
     invalid?.focus();
     form.reportValidity();