feat(school-detail): dedupe hero header, drop redundant chip strip

The hero header rendered the Ofsted signal twice — once as a chip in the
strip and again as a tile in the at-a-glance scorecard — and an
Oversubscribed chip already covered by the First-choice tile's footnote.

Remove the chip strip on both primary and secondary detail views, leaving
the scorecard trio (Results · Ofsted · First-choice) as the single home
for the headline numbers. Widen the scorecard's render gate to hasHeroStats
so a school with an Ofsted rating but no results still shows its Ofsted
signal (previously carried by the chip strip). Drop the now-dead .heroChip
CSS, keeping the shared .tone-* tokens the scorecard's serif number uses.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

nextjs-app/components/SecondarySchoolDetailView.tsx

@@ -192,6 +192,12 @@ export function SecondarySchoolDetailView({
   const heroAtt8Nat = secondaryAvg.attainment_8_score ?? null;
   const heroAcademicYear = latestResults ? formatAcademicYear(latestResults.year) : '';
 
+  // Scorecard renders if any tile has content, so a results-less school still
+  // shows its Ofsted signal (previously carried by the now-removed chip strip).
+  const hasHeroStats = heroAtt8 != null
+    || ofsted != null
+    || admissions?.first_preference_offer_pct != null;
+
   return (
     <div className={styles.container}>
       {/* ── Header ─────────────────────────────────────── */}
@@ -265,30 +271,10 @@ export function SecondarySchoolDetailView({
           </div>
         </div>
 
-        {/* Hero signal chips */}
-        <div className={styles.heroChips}>
-          <div className={`${styles.heroChip} ${styles[`tone-${ofstedHeroChip.tone}`]}`}>
-            <div className={styles.heroChipTitle}>{ofstedHeroChip.title}</div>
-            <div className={styles.heroChipSub}>{ofstedHeroChip.subtitle}</div>
-            {ofstedHeroChip.detail && (
-              <div className={styles.heroChipDetail}>{ofstedHeroChip.detail}</div>
-            )}
-          </div>
-
-          {admissions?.oversubscribed && (
-            <div className={`${styles.heroChip} ${styles['tone-coral']}`}>
-              <div className={styles.heroChipTitle}>Oversubscribed</div>
-              <div className={styles.heroChipSub}>
-                {admissions.first_preference_offer_pct != null
-                  ? `${Math.round(admissions.first_preference_offer_pct)}% of first-choice applicants offered a place`
-                  : 'More applicants than places'}
-              </div>
-            </div>
-          )}
-        </div>
-
-        {/* At-a-glance stats row */}
-        {latestResults && (
+        {/* At-a-glance stats row — the single home for the headline numbers.
+            Shows whenever any tile has content (results, Ofsted, or admissions),
+            so schools without KS4 results still carry their Ofsted signal. */}
+        {hasHeroStats && (
           <div className={styles.heroStats}>
             {heroAtt8 != null && (
               <div className={styles.heroStat}>