fix(search): badge inspected-but-ungraded schools as "Inspected", not "Not yet inspected"

A school inspected under the OEIF framework after September 2024 has an
inspection on record (ofsted_date set) but no overall_effectiveness grade,
since Ofsted no longer issues an overall judgement. buildOfstedListBadge
had no branch for this and fell through to "Not yet inspected", while the
detail page's hero chip correctly reported it as inspected — so the same
school read two contradictory ways.

Add an "Inspected · YYYY" branch that fires when an inspection is on record
(date or framework present) but no grade and not a Report Card, mirroring
the hero chip's fallback. Genuinely un-inspected schools (all Ofsted fields
null) still show "Not yet inspected". Add an .ofstedInspected badge style
(neutral slate) distinct from the grey pending state, and cover both cases
with tests.

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

nextjs-app/__tests__/lib/utils.test.ts

@@ -129,7 +129,21 @@ describe('buildOfstedListBadge', () => {
     expect(badge.cssClass).toBe('ofstedRc');
   });
 
-  it('returns pending badge when no grade and no ReportCard framework', () => {
+  it('returns an "Inspected" badge for an OEIF inspection with no overall grade (post-Sept-2024)', () => {
+    // Inspected after Sept 2024: inspection on record (date + framework) but
+    // Ofsted no longer issues an overall grade. Must NOT read as "Not yet inspected".
+    const badge = buildOfstedListBadge({ ofsted_grade: null, ofsted_date: '2024-11-01', ofsted_framework: 'OEIF' });
+    expect(badge.label).toBe('Inspected · 2024');
+    expect(badge.cssClass).toBe('ofstedInspected');
+  });
+
+  it('returns an "Inspected" badge without a year when the grade is missing and date is absent but a record exists', () => {
+    const badge = buildOfstedListBadge({ ofsted_grade: null, ofsted_date: null, ofsted_framework: 'OEIF' });
+    expect(badge.label).toBe('Inspected');
+    expect(badge.cssClass).toBe('ofstedInspected');
+  });
+
+  it('returns pending badge when no grade and no inspection on record', () => {
     const badge = buildOfstedListBadge({ ofsted_grade: null, ofsted_date: null, ofsted_framework: null });
     expect(badge.label).toBe('Not yet inspected');
     expect(badge.cssClass).toBe('ofstedPending');