fix(ofsted): link to the school's Ofsted page, not a hardcoded provider type

The report link hardcoded provider type 21, which 404s for every school
whose Ofsted provider type isn't 21 (nurseries -> 20, academies -> 23, etc.).
Use Ofsted's URN-based find-inspection-report URL, which redirects to the
correct provider page for any school, and rename the link to "Ofsted reports"
since it points to the school's Ofsted page (all reports), not one report.

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

nextjs-app/components/SchoolDetailView.tsx

@@ -504,14 +504,14 @@ export function SchoolDetailView({
               </span>
             )}
             <a
-              href={`https://reports.ofsted.gov.uk/provider/21/${schoolInfo.urn}`}
+              href={`https://reports.ofsted.gov.uk/inspection-reports/find-inspection-report/provider/ELS/${schoolInfo.urn}`}
               target="_blank"
               rel="noopener noreferrer"
               className={styles.ofstedReportLink}
               data-umami-event="external_link_clicked"
               data-umami-event-target="ofsted"
             >
-              Full report ↗
+              Ofsted reports ↗
             </a>
           </h2>