feat: signing order (#1290)

Adds the ability to specify an optional signing order for documents.
When specified a document will be considered sequential with recipients
only being allowed to sign in the order that they were specified in.

apps/web/src/app/embed/sign/[[...url]]/not-found.tsx

@@ -1,3 +1,3 @@
 export default function EmbedDirectTemplateNotFound() {
-  return <div>Not Found</div>
+  return <div>Not Found</div>;
 }