feat(rankings,metrics): score visible on phones; definitions usable everywhere (P2.2, P2.3)

Rankings mobile: the metric value — the point of the page — sat behind
a sideways swipe at 390px. The Area column now folds into a subline
under the school name, leaving Rank | School | Value to fit the
viewport with no horizontal scroll.

Rankings default metric becomes 'expected standard' (rwm_expected_pct);
'higher standard' stays available but no longer frames every school's
headline number in the terms parents least understand.

MetricTooltip was hover-only and display:none on phones — the mobile-
primary audience had zero access to the Attainment 8 / Progress 8 /
EBacc definitions. It is now a real button: tap/click/keyboard
toggleable with outside-click and Escape dismissal, 24px target,
shown at all viewports.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

nextjs-app/components/RankingsView.tsx

@@ -75,7 +75,7 @@ export function RankingsView({
   };
 
   const handlePhaseChange = (phase: string) => {
-    const defaultMetric = phase === 'secondary' ? 'attainment_8_score' : 'rwm_high_pct';
+    const defaultMetric = phase === 'secondary' ? 'attainment_8_score' : 'rwm_expected_pct';
     updateFilters({ phase, metric: defaultMetric });
   };
 
@@ -273,6 +273,11 @@ export function RankingsView({
                         <a href={schoolUrl(ranking.urn, ranking.school_name)} className={styles.schoolLink}>
                           {ranking.school_name}
                         </a>
+                        {/* On phones the Area column is hidden; the LA moves here
+                            so the metric value fits on screen without swiping. */}
+                        {ranking.local_authority && (
+                          <span className={styles.schoolCellArea}>{ranking.local_authority}</span>
+                        )}
                       </td>
                       <td className={styles.areaCell}>{ranking.local_authority || '-'}</td>
                       <td className={styles.typeCell}>{ranking.school_type || '-'}</td>