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/components/AdmissionsView.tsx

@@ -64,11 +64,11 @@ interface Step {
 const SECONDARY_STEPS: Step[] = [
   {
     title: 'Check entry criteria',
-    body: 'Look at each school\'s admissions policy — catchment areas, faith criteria, sibling priority, and aptitude tests vary widely.',
+    body: 'Look at each school\'s admissions policy. Catchment areas, faith criteria, sibling priority and aptitude tests vary widely.',
     callouts: [
       {
         title: 'Selective schools register earlier',
-        body: 'Grammar and other selective schools need separate entrance-test registration months earlier — often by September, well before the 31 October deadline.',
+        body: 'Grammar and other selective schools need separate entrance-test registration months earlier, often by September and well before the 31 October deadline.',
       },
       {
         title: 'Faith schools may need an extra form',
@@ -86,26 +86,26 @@ const SECONDARY_STEPS: Step[] = [
   {
     date: '31 October',
     title: 'Application deadline',
-    body: 'Submit your ranked list of schools — most councils allow three to six preferences (London boroughs typically six). Councils treat all preferences equally, so list schools in the genuine order you want them, not strategically.',
+    body: 'Submit your ranked list of schools. Most councils allow three to six preferences (London boroughs typically six). Councils treat all preferences equally, so list schools in the genuine order you want them, not strategically.',
     highlight: 'deadline',
     tool: { label: 'Compare performance to order your preferences', href: '/rankings' },
   },
   {
     date: '1 March',
     title: 'National Offer Day',
-    body: 'Your allocated school appears on the council\'s online admissions portal and is sent by email. Release times are set by each council — often from late afternoon, though some publish overnight — so check your council\'s page rather than refreshing at midnight.',
+    body: 'Your allocated school appears on the council\'s online admissions portal and is sent by email. Release times are set by each council (often from late afternoon, though some publish overnight), so check your council\'s page rather than refreshing at midnight.',
     highlight: 'offer',
     tool: { label: 'Look up your allocated school', href: '/' },
   },
   {
     date: '~15 March',
     title: 'Accept or decline',
-    body: 'Respond by the deadline your council gives — typically around 15 March. Accepting does not prevent you from keeping a place on a waiting list for a preferred school.',
+    body: 'Respond by the deadline your council gives, typically around 15 March. Accepting does not prevent you from keeping a place on a waiting list for a preferred school.',
     tool: { label: 'Weigh your offer against your other choices', href: '/compare' },
   },
   {
     title: 'Appeals',
-    body: 'If unsuccessful, you can appeal within 20 school days of the refusal letter. Secondary appeals consider whether prejudice to the school outweighs your case — success rates vary.',
+    body: 'If unsuccessful, you can appeal within 20 school days of the refusal letter. Secondary appeals consider whether prejudice to the school outweighs your case, and success rates vary.',
     tool: { label: 'Gather performance evidence for your case', href: '/rankings' },
   },
 ];
@@ -163,7 +163,7 @@ interface Tip {
 const TIPS: Tip[] = [
   {
     heading: 'Equal preference rule',
-    body: 'Councils consider every school you list before making any offer, then give you the highest-ranked one you qualify for. Your order only decides which qualifying school you get — you can\'t game it, so list schools in the order you genuinely want them.',
+    body: 'Councils consider every school you list before making any offer, then give you the highest-ranked one you qualify for. Your order only decides which qualifying school you get. You can\'t game it, so list schools in the order you genuinely want them.',
   },
   {
     heading: 'Late applications go to the back',
@@ -259,7 +259,7 @@ export function AdmissionsView() {
         </span>
         <h1 className={styles.heroTitle}>School Admissions Guide</h1>
         <p className={styles.heroSub}>
-          Everything parents need to know about applying for a school place in England — from opening dates to National Offer Day, with live countdowns to every key milestone.
+          Everything parents need to know about applying for a school place in England, from opening dates to National Offer Day, with live countdowns to every key milestone.
         </p>
       </section>