services module: review required attributes used to identify ApiPerson v2/v4

## Context

In `packages/modules/services/src/people/is-api-person.ts`, the required-attribute lists used to identify a person object per API version carry open questions:

```ts
const requiredApiPersonAttributes = {
[ApiVersion.v2]: [
'azureUniqueId',
/** TODO - has to be more required attributes to identify V2??? */
] satisfies Array>,
[ApiVersion.v4]: [
/** TODO - has to be more required attributes to identify V4??? */
'azureUniqueId',
] satisfies Array>,
};
```

Currently only `azureUniqueId` is checked for both v2 and v4, which may not be sufficient to reliably distinguish a valid `ApiPerson` from other objects that happen to have that field.

## Task

- Review the v2 and v4 People API contracts and decide whether additional required attributes should be checked to reliably identify a person object.
- Update `requiredApiPersonAttributes` accordingly, or confirm `azureUniqueId` alone is sufficient and remove the TODOs.

## File

`packages/modules/services/src/people/is-api-person.ts` (lines ~9, ~12)

Start in packages/modules/services/src/people/is-api-person.ts and compare its v2 and v4 attribute lists with the People API contracts. Decide whether azureUniqueId uniquely identifies each version, then update the lists or remove the TODOs; done when identification behavior matches the contracts.

Written by the indexing model from the issue text.