feat(admissions): publish the latest cut-off only, holding history back

Earlier years are to become a paid feature, so they stop being published.

The load-bearing part is that this is a change to the API, not only to the
page. /api/schools/{urn} is public and unauthenticated: leaving
admission_distance_history in the payload while declining to render it would
have handed the whole record to anyone who opened the network tab. It is
withheld at the source, and the page follows.

Nothing changes upstream. The tap, the plausibility band and
fact_admission_distance are untouched and still load every published year, so
restoring history for entitled callers is a change to one function in
data_loader rather than a re-collection.

What the reader now gets is the latest figure on the Admissions tile, and a
Distance section that answers the question the number alone cannot: whether
their own address falls inside it. Retitled to "How far away are you?", which
is what it now does — the previous title described a record that is no longer
there.

Removed with the history: the trend chart, the year-by-year table, the
per-year verdict strip, the trend summary and the coverage note, along with
their CSS. The section goes from 743px to 417px.

One consequence worth naming. A run of years used to soften a single close
call — a home just outside one year's cut-off was usually inside another. With
one year published, the "too close to call" band is the entire safety margin
between a parent and a place they do not have, so the verdict now names its
year, and the three outcomes are tinted apart rather than distinguished by
wording alone.

The existing stylesheet test earned its keep here: the three verdict classes
were referenced before they were written, and it caught them. Unstyled, a
"beyond the cut-off" result would have been indistinguishable from an "inside"
one — the exact failure the longhand class map was written to prevent.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WDvkyqqHABm4bmth2kjAxE

nextjs-app/__tests__/components/lastDistanceOffered.test.tsx

@@ -89,128 +89,68 @@ describe('secondary detail page', () => {
   });
 });
 
-// ── The Distance view ──────────────────────────────────────────────────
+// ── The Distance section ───────────────────────────────────────────────
 
-const history = (pts: [number, number][]): SchoolAdmissionDistance[] =>
-  pts.map(([year, distance_m]) => ({
-    year, distance_m, route_count: 1, la_name: 'Camden', distance_unit_raw: 'miles',
-  }));
-
-describe('primary Distance section', () => {
-  it('appears as its own section once there are two or more published years', () => {
-    // Not a third tab inside Admissions: stacking a 1402px view in the
-    // admissions viewport sized the whole card to it and left the default view
-    // as four tiles in ~1080px of blank card.
+describe('Distance section', () => {
+  it('appears for a school with a figure and coordinates', () => {
     const { container } = renderSchoolDetail({
       ...primaryFixture,
-      admissionDistance: cutoff({ distance_m: 700, year: 2024 }),
-      admissionDistanceHistory: history([[2021, 1000], [2022, 900], [2023, 800], [2024, 700]]),
+      schoolInfo: { ...primaryFixture.schoolInfo, latitude: 51.5, longitude: -0.12 },
+      admissionDistance: cutoff({ distance_m: 700, year: 2026 }),
     });
 
     expect(container.querySelector('#distance')).toBeInTheDocument();
-    expect(screen.getByText('How far the last place went')).toBeInTheDocument();
-    // And it did not come back as a tab.
-    expect(screen.queryByRole('button', { name: 'Distance' })).not.toBeInTheDocument();
+    expect(screen.getByText('How far away are you?')).toBeInTheDocument();
   });
 
-  it('stays away on a single published year', () => {
-    // One point is a fact, not a history; a chart of it invites a trend reading
-    // that is not there.
+  it('stays away when the school has no coordinates to measure from', () => {
     const { container } = renderSchoolDetail({
       ...primaryFixture,
-      admissionDistance: cutoff({ distance_m: 700, year: 2024 }),
-      admissionDistanceHistory: history([[2024, 700]]),
+      schoolInfo: { ...primaryFixture.schoolInfo, latitude: null, longitude: null },
+      admissionDistance: cutoff({ distance_m: 700, year: 2026 }),
     });
 
     expect(container.querySelector('#distance')).not.toBeInTheDocument();
   });
 
-  it('lists every year in the span, including the ones with no figure', () => {
-    renderSchoolDetail({
+  it('stays away when no figure has been published', () => {
+    const { container } = renderSchoolDetail({
       ...primaryFixture,
-      admissionDistance: cutoff({ distance_m: 700, year: 2024 }),
-      admissionDistanceHistory: history([[2021, 1000], [2024, 700]]),
+      schoolInfo: { ...primaryFixture.schoolInfo, latitude: 51.5, longitude: -0.12 },
+      admissionDistance: null,
     });
 
-    // 2022 and 2023 were never published but must still appear as rows, or the
-    // gap in the chart has nothing explaining it.
-    for (const year of ['2021', '2022', '2023', '2024']) {
-      expect(screen.getByRole('rowheader', { name: year })).toBeInTheDocument();
-    }
-    expect(screen.getAllByText('Not published').length).toBe(2);
+    expect(container.querySelector('#distance')).not.toBeInTheDocument();
   });
 
-  it('never claims everyone was offered a place', () => {
-    // fact_admissions.oversubscribed is about first preferences only, so the
-    // stronger claim is not supported by the data behind it.
-    renderSchoolDetail({
-      ...primaryFixture,
-      admissionDistance: cutoff({ distance_m: 700, year: 2024 }),
-      admissionDistanceHistory: history([[2021, 1000], [2024, 700]]),
-      admissionsHistory: [
-        ...primaryFixture.admissionsHistory,
-        { year: 2022, oversubscribed: false, places_offered: 60 },
-      ],
-    });
-
-    expect(screen.getByText(/Places available on first preferences/)).toBeInTheDocument();
-    expect(screen.queryByText(/every applicant/i)).not.toBeInTheDocument();
-    expect(screen.queryByText(/all offered/i)).not.toBeInTheDocument();
-  });
-
-  it('draws the chart only once it will also state a direction', () => {
-    const four = renderSchoolDetail({
-      ...primaryFixture,
-      admissionDistance: cutoff({ distance_m: 700, year: 2024 }),
-      admissionDistanceHistory: history([[2021, 1000], [2022, 900], [2023, 800], [2024, 700]]),
-    });
-    expect(screen.getByText(/Last distance offered, by year/)).toBeInTheDocument();
-    four.unmount();
-
-    renderSchoolDetail({
-      ...primaryFixture,
-      admissionDistance: cutoff({ distance_m: 700, year: 2024 }),
-      admissionDistanceHistory: history([[2023, 800], [2024, 700]]),
-    });
-    expect(screen.queryByText(/Last distance offered, by year/)).not.toBeInTheDocument();
-  });
-
-  it('states the caveat exactly once, even though the check also renders', () => {
+  it('shows no year-by-year record — that is held back as a paid feature', () => {
+    // The page must not leak the history through a table, a chart or a strip of
+    // per-year verdicts. The API no longer sends it either; this guards the
+    // render side so a future component cannot quietly put it back.
     renderSchoolDetail({
       ...primaryFixture,
       schoolInfo: { ...primaryFixture.schoolInfo, latitude: 51.5, longitude: -0.12 },
-      admissionDistance: cutoff({ distance_m: 700, year: 2024 }),
-      admissionDistanceHistory: history([[2021, 1000], [2024, 700]]),
+      admissionDistance: cutoff({ distance_m: 700, year: 2026 }),
     });
 
-    expect(screen.getAllByText(/Distance is the last criterion/)).toHaveLength(1);
-  });
-
-  it('withholds a trend reading while the record is thin', () => {
-    renderSchoolDetail({
-      ...primaryFixture,
-      admissionDistance: cutoff({ distance_m: 700, year: 2024 }),
-      admissionDistanceHistory: history([[2023, 800], [2024, 700]]),
-    });
-
-    expect(screen.getByText(/too few to read as a trend/)).toBeInTheDocument();
-    expect(screen.queryByText(/Across \d+ published years/)).not.toBeInTheDocument();
+    // Scoped to the section: the page has other tables (the history section's).
+    const section = document.querySelector('#distance')!;
+    expect(section.querySelector('table')).toBeNull();
+    expect(screen.queryByText(/Last distance offered, by year/)).not.toBeInTheDocument();
+    expect(screen.queryByText(/Not published/)).not.toBeInTheDocument();
+    expect(screen.queryByText(/too few to read as a trend/)).not.toBeInTheDocument();
   });
 });
 
 describe('secondary Distance section', () => {
-  it('renders as its own section once there are two published years', () => {
-    renderSecondarySchoolDetail({
+  it('renders on the secondary template too', () => {
+    const { container } = renderSecondarySchoolDetail({
       ...secondaryFixture,
-      admissionDistance: cutoff({ distance_m: 3472.96 }),
-      admissionDistanceHistory: history([[2023, 3800], [2024, 3472.96]]),
+      schoolInfo: { ...secondaryFixture.schoolInfo, latitude: 51.5, longitude: -0.12 },
+      admissionDistance: cutoff({ distance_m: 3472.96, year: 2026 }),
     });
 
-    expect(screen.getByRole('rowheader', { name: '2023' })).toBeInTheDocument();
-    // Two points is below the threshold that lets us state a direction, so no
-    // chart is drawn — a line through three points asserts a trend the
-    // summary underneath would refuse to.
-    expect(screen.queryByText(/Last distance offered, by year/)).not.toBeInTheDocument();
+    expect(container.querySelector('#distance')).toBeInTheDocument();
   });
 
   it('explains a selective school by how it admits rather than as missing data', () => {
@@ -218,7 +158,6 @@ describe('secondary Distance section', () => {
       ...secondaryFixture,
       schoolInfo: { ...secondaryFixture.schoolInfo, admissions_policy: 'Selective' },
       admissionDistance: null,
-      admissionDistanceHistory: [],
     });
 
     expect(screen.getByText(/ranked by the entrance test/)).toBeInTheDocument();
@@ -229,7 +168,6 @@ describe('secondary Distance section', () => {
     renderSecondarySchoolDetail({
       ...secondaryFixture,
       admissionDistance: null,
-      admissionDistanceHistory: [],
       admissionsHistory: [
         { year: 2022, oversubscribed: false },
         { year: 2023, oversubscribed: false },