feat(detail): move religious character into header details + mobile reveal

Religious character now sits with the other labelled header details (near
County / Constituency) as "Religious character: <denomination>" ("None" for
Does not apply / None), instead of as an identity chip.

On mobile/tablet (≤768px) the header details block was hidden outright; it's
now collapsed behind a "Show all details" toggle that reveals the full block
(headteacher, website, pupils, trust, phone, religious character, county,
constituency). Applied to both the primary and secondary detail views for
parity. Extends the e2e journey with the mobile toggle behaviour.

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

nextjs-app/components/SecondarySchoolDetailView.module.css

@@ -207,6 +207,22 @@
     text-decoration: underline;
 }
 
+/* "Show all details" reveal — only rendered on mobile/tablet, where the
+   header details block is collapsed below the fold. Hidden on desktop. */
+.detailsToggle {
+    display: none;
+    align-items: center;
+    gap: 0.25rem;
+    margin-top: 0.5rem;
+    padding: 0;
+    background: none;
+    border: none;
+    font-size: 0.8125rem;
+    font-weight: 600;
+    color: var(--accent-teal, #2d7d7d);
+    cursor: pointer;
+}
+
 .actions {
     display: flex;
     gap: 0.5rem;
@@ -1066,7 +1082,18 @@
         padding: 0.1rem 0.375rem;
     }
 
+    /* Collapsed below the fold on phones/tablets; revealed via "Show all
+       details" so the metrics surface sooner. */
+    .detailsToggle {
+        display: inline-flex;
+    }
+
     .headerDetails {
+        display: none;
+    }
+
+    .headerDetailsOpen {
+        display: flex;
         flex-direction: column;
         gap: 0.375rem;
     }