make name and username required

prisma/schema.prisma

@@ -82,8 +82,8 @@ model Session {
 
 model User {
   id       String    @id @default(auto()) @map("_id") @db.ObjectId
-  name     String?
-  username String?   @unique
+  name     String
+  username String    @unique
   password String
   sessions Session[]
 }