fix(frontend): format 6-digit EES academic year codes correctly

formatAcademicYear now handles both 4-digit (2023→2023/24) and 6-digit
EES codes (202526→2025/26). Applied to all year displays: SATs, phonics,
admissions, finances, and the yearly results table.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

nextjs-app/components/SchoolDetailView.tsx

@@ -15,7 +15,7 @@ import type {
   SchoolAdmissions, SenDetail, Phonics,
   SchoolDeprivation, SchoolFinance,
 } from '@/lib/types';
-import { formatPercentage, formatProgress } from '@/lib/utils';
+import { formatPercentage, formatProgress, formatAcademicYear } from '@/lib/utils';
 import styles from './SchoolDetailView.module.css';
 
 const OFSTED_LABELS: Record<number, string> = {
@@ -331,7 +331,7 @@ export function SchoolDetailView({
       {/* SATs Results (merged with Subject Breakdown) */}
       {latestResults && (
         <section id="sats" className={styles.card}>
-          <h2 className={styles.sectionTitle}>SATs Results ({latestResults.year})</h2>
+          <h2 className={styles.sectionTitle}>SATs Results ({formatAcademicYear(latestResults.year)})</h2>
           <p className={styles.sectionSubtitle}>
             End-of-primary-school tests taken by Year 6 pupils. National averages shown for comparison.
           </p>
@@ -458,7 +458,7 @@ export function SchoolDetailView({
       {/* Year 1 Phonics */}
       {hasPhonics && phonics && (
         <section id="phonics" className={styles.card}>
-          <h2 className={styles.sectionTitle}>Year 1 Phonics ({phonics.year})</h2>
+          <h2 className={styles.sectionTitle}>Year 1 Phonics ({formatAcademicYear(phonics.year)})</h2>
           <p className={styles.sectionSubtitle}>
             Phonics is a key early reading skill. Children are tested at the end of Year 1.
           </p>
@@ -511,7 +511,7 @@ export function SchoolDetailView({
       {/* How Hard to Get In */}
       {admissions && (
         <section id="admissions" className={styles.card}>
-          <h2 className={styles.sectionTitle}>How Hard to Get Into This School ({admissions.year})</h2>
+          <h2 className={styles.sectionTitle}>How Hard to Get Into This School ({formatAcademicYear(admissions.year)})</h2>
           <div className={styles.metricsGrid}>
             {admissions.published_admission_number != null && (
               <div className={styles.metricCard}>
@@ -631,7 +631,7 @@ export function SchoolDetailView({
       {/* Finances */}
       {hasFinance && finance && (
         <section id="finances" className={styles.card}>
-          <h2 className={styles.sectionTitle}>School Finances ({finance.year})</h2>
+          <h2 className={styles.sectionTitle}>School Finances ({formatAcademicYear(finance.year)})</h2>
           <p className={styles.sectionSubtitle}>
             Per-pupil spending shows how much the school has to spend on each child&apos;s education.
           </p>
@@ -685,7 +685,7 @@ export function SchoolDetailView({
                   <tbody>
                     {yearlyData.map((result) => (
                       <tr key={result.year}>
-                        <td className={styles.yearCell}>{result.year}</td>
+                        <td className={styles.yearCell}>{formatAcademicYear(result.year)}</td>
                         <td>{result.rwm_expected_pct !== null ? formatPercentage(result.rwm_expected_pct) : '-'}</td>
                         <td>{result.rwm_high_pct !== null ? formatPercentage(result.rwm_high_pct) : '-'}</td>
                         <td>{result.reading_progress !== null ? formatProgress(result.reading_progress) : '-'}</td>

nextjs-app/lib/utils.ts

@@ -338,9 +338,15 @@ export function parseQueryString(search: string): Record<string, string> {
 // ============================================================================
 
 /**
- * Format academic year (e.g., 2023 -> "2023/24")
+ * Format academic year.
+ * Handles both 4-digit start years (2023 → "2023/24") and
+ * 6-digit EES codes (202526 → "2025/26").
  */
 export function formatAcademicYear(year: number): string {
+  const s = year.toString();
+  if (s.length === 6) {
+    return `${s.slice(0, 4)}/${s.slice(4)}`;
+  }
   const nextYear = (year + 1).toString().slice(-2);
   return `${year}/${nextYear}`;
 }