API: include current_title / current_school on the nested person in project-people

[jonfroehlich]

Summary

/api/v1/projects/<slug>/people/ nests a person object that carries name, url, url_name, thumbnail, and
image_original — but not current_title or current_school. Both are already on PersonSerializer and both are
already cached_property on the model, so this is a nested-serializer field list change, not new data.

Why

Project Sidewalk's About page (ProjectSidewalk/SidewalkWebpage#4664) renders the current-team cards from the project
roster. Each card wants the member's title and affiliation as they are today ("Professor · University of
Washington"), which is exactly current_title / current_school — the project row's position_title is frozen at the
position they held when the stint began, so it's only a fallback.

Because those two fields live only on the person-detail endpoint, the page has to issue one extra request per active
member just to fill in two strings. That's 11 requests today on top of the roster fetch, and it grows with the team:

GET /api/v1/projects/sidewalk/people/            (2 pages)
GET /api/v1/people/jonfroehlich/                 ┐
GET /api/v1/people/mikeysaugstad/                │ 11 requests, 2 fields each
GET /api/v1/people/yochaieisenberg/              │
...                                              ┘

They're issued concurrently and cached client-side, so this isn't urgent — but it's 11 round-trips to your server per
cold visit for data you already serialize elsewhere, and every one of them is a chance for a card to render without its
title.

This is the same shape as #1432, which added the cropped thumbnail to both the person endpoint and the nested
person object for exactly this reason.

Proposed change

Add current_title and current_school to whichever nested/summary person serializer
ProjectRoleSerializer.person uses. current_department would be free alongside them (Person.get_current_department
exists), though the About page doesn't need it.

If you'd rather not widen the nested object for every consumer, an alternative that also works: accept a
?expand=person (or similar) on the project-people endpoint. Either is fine on our end — the consumer change is a few
lines and deleting a Promise.allSettled block.

Consumer

public/js/aboutPage.js (#renderTeam) in ProjectSidewalk/SidewalkWebpage, covered by test/js/aboutPage.test.js,
which pins the payload shapes of /api/v1/projects/sidewalk/people/, /api/v1/people/<url_name>/,
/api/v1/projects/sidewalk/publications/, and /api/v1/projects/sidewalk/grants/. If any of those shapes change,
those tests are where it surfaces.

Follow-on to #1426 and #1432, both of which landed and are working well — the About page now renders contributor
credentials ("Undergrad, UW") and cropped headshots straight off this API.

Unrelated note, carried over from #1426

The per-project role is still blank for most of the 11 people currently active on Project Sidewalk, so their role line
falls back to current_title — which is why the page reads "Director" for Judy Shanley rather than anything about her
role on the project. That one's a data-entry fix in the admin, not code.

[jonfroehlich]

Addressed in #1436 — but by fixing the roster's own fields rather than adding current_* to the nested person.

The actual defect: position_title / position_school on /projects/<slug>/people/ are pinned to the Position held on the role's start date (#1426's rule). A role open since 2012 reports a 2012 title, which is why the About page has to go fetch current_title per member. On prod today my Sidewalk row reads Assistant Professor / UMD (role 2012-02-01 → open) while /people/jonfroehlich/ reads Professor / University of Washington.

The fix: position_during_role now resolves the latest Position overlapping the role's window [start_date, end_date or today]. Ongoing role → today's title; a stint that ended in 2016 still reads what that person was in 2016, never their post-lab title. So the roster is right on its own terms, project-scoped, and Sidewalk can delete the Promise.allSettled block.

Why not the nested current_*: it's project-agnostic, and for an alum it's their last lab position rather than today's employer — wrong for a past-contributor card in a different way. It also lives on PersonSummarySerializer, which is nested in every publication's authors; that endpoint doesn't prefetch position_set, so it'd go N+1 on a list of pubs for a field nobody there reads.

⚠️ Heads up for ProjectSidewalk/SidewalkWebpage#4664: position_title / position_school values change for roles spanning a title change (that's the point). Names and types are untouched, so the shape assertions in test/js/aboutPage.test.js still hold.

The blank per-project role for most active Sidewalk members is still a data-entry fix in the admin — not touched here.