capture role_in_org + additional_roles_in_org on fetch_users_in_org

[mrmauer]

After PR

When calling fetch_users_in_org, the role information for that org member will be included at the top of the returned UserMetadata. This information is already embedded in org_id_to_org_info, but this provides a better DX and our BE already returns it.

Notably, for every other instance of UserMetadata role_in_org.is_none() and additional_roles_in_org.is_none(), so a new type may make more sense, but I decided to favor the back-compatible fix here.

Tests

Verified the following in an example app:

1. When using fetch_users_in_org the UserMetadata includes role_in_org: Some("Value") and additional_roles_in_org: Some([]).
2. When using fetch_user_by_id the UserMetadata has the default role_in_org: None and additional_roles_in_org: None.

[pfvatterott]

LGTM