copy(web): replace em dashes in public copy

Rewrites every visitor-facing string that used an em dash, choosing the
punctuation for what the dash was doing: a colon before a list or
explanation, a comma for an aside, a full stop between two thoughts,
parentheses for an aside mid-sentence. Covers page titles and meta
descriptions, the home and admissions guide copy, school page headings
and notes, the compare page, metric labels and tooltips.

Two rewrites also fix the sentence around them: the closure banner no
longer repeats "proposed for closure", and the cut-off caveat's list of
priorities now parses.

A lone dash marking a missing value in a table cell stays: it is a data
convention, not prose. A Jest guard walks the source with the TypeScript
parser and fails on any other em dash in a string or JSX text node.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

nextjs-app/app/(frontend)/compare/page.tsx

@@ -33,7 +33,7 @@ export async function generateMetadata(
     // Deliberately not the homepage's phrase. Two pages chasing "compare
     // schools" is how a site competes with itself; this one takes the tool
     // phrasing instead.
-    title: 'School Comparison Tool — Up to Five at Once | schoolcompare',
+    title: 'School Comparison Tool: Up to Five Schools at Once | schoolcompare',
     description:
       'Put up to five English schools in one table: SATs and GCSE results against the England average, Ofsted grades, and the distance places were offered.',
     keywords:

nextjs-app/app/(frontend)/layout.tsx

@@ -54,7 +54,7 @@ export const metadata: Metadata = {
     template: '%s | schoolcompare',
   },
   description:
-    'Put five English schools on one screen — SATs, GCSE results, Ofsted grades, and how close you had to live to get a place. Free, no sign-up.',
+    'Put five English schools on one screen: SATs, GCSE results, Ofsted grades, and how close you had to live to get a place. Free, no sign-up.',
   keywords: 'school comparison, KS2 results, KS4 results, primary school, secondary school, England schools, SATs results, GCSE results',
   authors: [{ name: 'schoolcompare' }],
   manifest: '/manifest.json',
@@ -69,7 +69,7 @@ export const metadata: Metadata = {
     type: 'website',
     title: 'Compare Schools Side by Side | schoolcompare',
     description:
-      'Put five English schools on one screen — SATs, GCSE results, Ofsted grades, and how close you had to live to get a place.',
+      'Put five English schools on one screen: SATs, GCSE results, Ofsted grades, and how close you had to live to get a place.',
     /*
      * Declared, not inherited.
      *
@@ -93,7 +93,7 @@ export const metadata: Metadata = {
     card: 'summary_large_image',
     title: 'Compare Schools Side by Side | schoolcompare',
     description:
-      'Put five English schools on one screen — SATs, GCSE results, Ofsted grades, and how close you had to live to get a place.',
+      'Put five English schools on one screen: SATs, GCSE results, Ofsted grades, and how close you had to live to get a place.',
     // The card is summary_large_image; claiming that and supplying no image
     // is worse than claiming a summary card.
     images: ['/opengraph-image'],

nextjs-app/app/(frontend)/page.tsx

@@ -49,7 +49,7 @@ export const metadata: Metadata = {
    */
   title: { absolute: 'Compare Schools Side by Side | schoolcompare' },
   description:
-    'Put five English schools on one screen — SATs, GCSE results, Ofsted grades, and how close you had to live to get a place. Free, no sign-up.',
+    'Put five English schools on one screen: SATs, GCSE results, Ofsted grades, and how close you had to live to get a place. Free, no sign-up.',
   // This page reads eleven search params. They filter a result set; they do
   // not make a new document. Collapsing every combination onto "/" stops the
   // homepage competing with itself for its own head terms.

nextjs-app/app/(frontend)/schools/[place]/page.tsx

@@ -56,7 +56,7 @@ export async function generateMetadata({ params }: Props): Promise<Metadata> {
     // absolute: the root layout's template appends '| schoolcompare' to a
     // plain string, and this title already carries it. Without this every
     // place title read '... | schoolcompare | schoolcompare'.
-    title: { absolute: `Schools in ${name} — Compare ${count} Schools | schoolcompare` },
+    title: { absolute: `Schools in ${name}: Compare ${count} Schools | schoolcompare` },
     description:
       `Every school in ${name}, with SATs and GCSE results, Ofsted grades, the local `
       + `average against England, and how close you had to live to get a place.`,

nextjs-app/app/(frontend)/schools/authority/[la]/[phase]/page.tsx

@@ -41,7 +41,7 @@ export async function generateMetadata({ params }: Props): Promise<Metadata> {
     // "Local Authority" stays in the title for the same reason it is on the
     // bare authority page: 67 town names collide with an authority name, and
     // a reader landing on both needs to know which set each covers.
-    title: { absolute: `${word} Schools in ${name} — Local Authority | schoolcompare` },
+    title: { absolute: `${word} Schools in ${name} (Local Authority) | schoolcompare` },
     description:
       `Every ${phase} school in the ${name} local authority, with results, Ofsted `
       + `grades and the authority average against England.`,

nextjs-app/app/(frontend)/schools/authority/[la]/page.tsx

@@ -43,7 +43,7 @@ export async function generateMetadata({ params }: Props): Promise<Metadata> {
 
   const { name, count } = detail.place;
   return {
-    title: { absolute: `Schools in ${name} — Local Authority | schoolcompare` },
+    title: { absolute: `Schools in ${name} (Local Authority) | schoolcompare` },
     description:
       `All ${count} schools in the ${name} local authority, with SATs and GCSE results, `
       + `Ofsted grades and the authority average against England.`,

nextjs-app/app/opengraph-image.tsx

@@ -11,7 +11,7 @@ import { ImageResponse } from 'next/og';
  * and a suggestion of the illustration's rolling landscape along the bottom.
  * It states the promise rather than decorating it.
  */
-export const alt = 'schoolcompare — find the school where your child will flourish';
+export const alt = 'schoolcompare: find the school where your child will flourish';
 export const size = { width: 1200, height: 630 };
 export const contentType = 'image/png';