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How do I share a type between a client and server, but make a specific field optional for one and required for the other??

Let's say I have a client/server application with a data structure on the server side:

```typescript
type User = {
  name: string;
  superSecretGovernmentIdNumber: string;
};
```

These fields are both non-nullable; all users in this system have a `name` and a `superSecretGovernmentIdNumber`, and the server always knows what both are.

On the client, I'd like to be able to use this same type, with non-nullable `name`, but depending on whether the user you're viewing is yourself or another person, you may or may not be able to see that user's `superSecretGovernmentIdNumber`. That is, I would like the same type to be this on the client:

```typescript
type User = {
  name: string;
  superSecretGovernmentIdNumber?: string;
};
```

There is `Partial<T>`, which would make *everything* optional, but I still want `name` to be required.

Is this expressible in TypeScript? How?