fix: allow nullable document audit logs (#2682)

packages/prisma/migrations/20260408052212_add_set_null_for_audit_log_foreign_key/migration.sql

@@ -0,0 +1,8 @@
+-- DropForeignKey
+ALTER TABLE "DocumentAuditLog" DROP CONSTRAINT "DocumentAuditLog_envelopeId_fkey";
+
+-- AlterTable
+ALTER TABLE "DocumentAuditLog" ALTER COLUMN "envelopeId" DROP NOT NULL;
+
+-- AddForeignKey
+ALTER TABLE "DocumentAuditLog" ADD CONSTRAINT "DocumentAuditLog_envelopeId_fkey" FOREIGN KEY ("envelopeId") REFERENCES "Envelope"("id") ON DELETE SET NULL ON UPDATE CASCADE;

packages/prisma/schema.prisma

@@ -466,7 +466,7 @@ model EnvelopeItem {
 
 model DocumentAuditLog {
   id         String   @id @default(cuid())
-  envelopeId String
+  envelopeId String?
   createdAt  DateTime @default(now())
   type       String
   data       Json
@@ -478,7 +478,7 @@ model DocumentAuditLog {
   userAgent String?
   ipAddress String?
 
-  envelope Envelope @relation(fields: [envelopeId], references: [id], onDelete: Cascade)
+  envelope Envelope? @relation(fields: [envelopeId], references: [id], onDelete: SetNull)
 
   @@index([envelopeId])
 }