fix: reverse meta relation and tidy code

packages/lib/server-only/document-meta/upsert-document-meta.ts

@@ -0,0 +1,30 @@
+'use server';
+
+import { prisma } from '@documenso/prisma';
+
+export type CreateDocumentMetaOptions = {
+  documentId: number;
+  subject: string;
+  message: string;
+};
+
+export const upsertDocumentMeta = async ({
+  subject,
+  message,
+  documentId,
+}: CreateDocumentMetaOptions) => {
+  return await prisma.documentMeta.upsert({
+    where: {
+      documentId,
+    },
+    create: {
+      subject,
+      message,
+      documentId,
+    },
+    update: {
+      subject,
+      message,
+    },
+  });
+};