add index to gateway id on service envelopes table

prisma/migrations/20240316060749_add_index_to_gateway_id_on_service_envelopes_table/migration.sql

@@ -0,0 +1,2 @@
+-- CreateIndex
+CREATE INDEX `service_envelopes_gateway_id_idx` ON `service_envelopes`(`gateway_id`);

prisma/schema.prisma

@@ -114,6 +114,7 @@ model ServiceEnvelope {
 
   @@index(created_at)
   @@index(updated_at)
+  @@index(gateway_id)
   @@map("service_envelopes")
 }