feat(seo): add school name to URLs, fix sticky nav, collapse compare widget

- URLs now /school/138267-school-name instead of /school/138267
- Bare URN URLs redirect to canonical slug (backward compat)
- Remove overflow-x:hidden that broke sticky tab nav on secondary pages
- ComparisonToast starts collapsed — user must click to open

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

nextjs-app/app/school/[slug]/page.tsx

@@ -0,0 +1,165 @@
+/**
+ * Individual School Page (SSR)
+ * Dynamic route for school details with full SEO optimization
+ * URL format: /school/138267-school-name-here
+ */
+
+import { fetchSchoolDetails } from '@/lib/api';
+import { notFound, redirect } from 'next/navigation';
+import { SchoolDetailView } from '@/components/SchoolDetailView';
+import { SecondarySchoolDetailView } from '@/components/SecondarySchoolDetailView';
+import { parseSchoolSlug, schoolUrl } from '@/lib/utils';
+import type { Metadata } from 'next';
+
+interface SchoolPageProps {
+  params: Promise<{ slug: string }>;
+}
+
+export async function generateMetadata({ params }: SchoolPageProps): Promise<Metadata> {
+  const { slug } = await params;
+  const urn = parseSchoolSlug(slug);
+
+  if (!urn || urn < 100000 || urn > 999999) {
+    return {
+      title: 'School Not Found',
+    };
+  }
+
+  try {
+    const data = await fetchSchoolDetails(urn);
+    const { school_info } = data;
+
+    const canonicalPath = schoolUrl(urn, school_info.school_name);
+    const isSecondary = (school_info.phase ?? '').toLowerCase().includes('secondary')
+      || (data.yearly_data ?? []).some((d: any) => d.attainment_8_score != null);
+    const title = `${school_info.school_name} | ${school_info.local_authority || 'England'}`;
+    const description = isSecondary
+      ? `View GCSE results, Attainment 8, Progress 8 and school statistics for ${school_info.school_name}${school_info.local_authority ? ` in ${school_info.local_authority}` : ''}.`
+      : `View KS2 performance data, results, and statistics for ${school_info.school_name}${school_info.local_authority ? ` in ${school_info.local_authority}` : ''}. Compare reading, writing, and maths results.`;
+
+    return {
+      title,
+      description,
+      keywords: isSecondary
+        ? `${school_info.school_name}, GCSE results, secondary school, ${school_info.local_authority}, Attainment 8, Progress 8`
+        : `${school_info.school_name}, KS2 results, primary school, ${school_info.local_authority}, school performance, SATs results`,
+      openGraph: {
+        title,
+        description,
+        type: 'website',
+        url: `https://schoolcompare.co.uk${canonicalPath}`,
+        siteName: 'SchoolCompare',
+      },
+      twitter: {
+        card: 'summary',
+        title,
+        description,
+      },
+      alternates: {
+        canonical: `https://schoolcompare.co.uk${canonicalPath}`,
+      },
+    };
+  } catch {
+    return {
+      title: 'School Not Found',
+    };
+  }
+}
+
+// Force dynamic rendering
+export const dynamic = 'force-dynamic';
+
+export default async function SchoolPage({ params }: SchoolPageProps) {
+  const { slug } = await params;
+  const urn = parseSchoolSlug(slug);
+
+  // Validate URN format
+  if (!urn || urn < 100000 || urn > 999999) {
+    notFound();
+  }
+
+  // Fetch school data
+  let data;
+  try {
+    data = await fetchSchoolDetails(urn);
+  } catch (error) {
+    console.error(`Failed to fetch school ${urn}:`, error);
+    notFound();
+  }
+
+  const { school_info, yearly_data, absence_data, ofsted, parent_view, census, admissions, sen_detail, phonics, deprivation, finance } = data;
+
+  // Redirect bare URN to canonical slug URL
+  const canonicalSlug = schoolUrl(urn, school_info.school_name).replace('/school/', '');
+  if (slug !== canonicalSlug) {
+    redirect(`/school/${canonicalSlug}`);
+  }
+
+  const isSecondary = (school_info.phase ?? '').toLowerCase().includes('secondary')
+    || yearly_data.some((d: any) => d.attainment_8_score != null);
+
+  // Generate JSON-LD structured data for SEO
+  const structuredData = {
+    '@context': 'https://schema.org',
+    '@type': 'EducationalOrganization',
+    name: school_info.school_name,
+    identifier: school_info.urn.toString(),
+    ...(school_info.address && {
+      address: {
+        '@type': 'PostalAddress',
+        streetAddress: school_info.address,
+        addressLocality: school_info.local_authority || undefined,
+        postalCode: school_info.postcode || undefined,
+        addressCountry: 'GB',
+      },
+    }),
+    ...(school_info.latitude && school_info.longitude && {
+      geo: {
+        '@type': 'GeoCoordinates',
+        latitude: school_info.latitude,
+        longitude: school_info.longitude,
+      },
+    }),
+    ...(school_info.school_type && {
+      additionalType: school_info.school_type,
+    }),
+  };
+
+  return (
+    <>
+      <script
+        type="application/ld+json"
+        dangerouslySetInnerHTML={{ __html: JSON.stringify(structuredData) }}
+      />
+      {isSecondary ? (
+        <SecondarySchoolDetailView
+          schoolInfo={school_info}
+          yearlyData={yearly_data}
+          absenceData={absence_data}
+          ofsted={ofsted ?? null}
+          parentView={parent_view ?? null}
+          census={census ?? null}
+          admissions={admissions ?? null}
+          senDetail={sen_detail ?? null}
+          phonics={phonics ?? null}
+          deprivation={deprivation ?? null}
+          finance={finance ?? null}
+        />
+      ) : (
+        <SchoolDetailView
+          schoolInfo={school_info}
+          yearlyData={yearly_data}
+          absenceData={absence_data}
+          ofsted={ofsted ?? null}
+          parentView={parent_view ?? null}
+          census={census ?? null}
+          admissions={admissions ?? null}
+          senDetail={sen_detail ?? null}
+          phonics={phonics ?? null}
+          deprivation={deprivation ?? null}
+          finance={finance ?? null}
+        />
+      )}
+    </>
+  );
+}