feat(compare): fill the sticky bar's label rail with a comparison caption

'COMPARING / 3 primary schools' — 0.72rem uppercase eyebrow over a
0.95rem semibold count, sized to sit alongside the 0.92rem chip names
without dominating. Desktop only; mobile pills unchanged.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0146VHeLAWjDVE2B5uU67jCB

nextjs-app/components/ComparisonView.module.css

@@ -148,10 +148,16 @@
   text-overflow: ellipsis;
 }
 
+/* Caption filling the label rail on desktop ("Comparing / 3 primary
+   schools"). Hidden on mobile, where the bar is a row of compact pills. */
+.barCaption {
+  display: none;
+}
+
 /* Desktop (matches the sections' 761px breakpoint): the bar adopts the same
    grid template as compareSections' .grid — a 200px row-label rail plus one
    column per school — so each chip sits exactly over the column it labels.
-   The first chip starts after the empty label rail. */
+   The caption occupies the rail; chips flow into the school columns. */
 @media (min-width: 761px) {
   .schoolBar {
     display: grid;
@@ -164,8 +170,29 @@
     min-width: 0;
   }
 
-  .schoolChip:first-child {
-    grid-column: 2;
+  .barCaption {
+    grid-column: 1;
+    display: flex;
+    flex-direction: column;
+    justify-content: center;
+    gap: 0.1rem;
+    padding-right: 0.5rem;
+    min-width: 0;
+  }
+
+  .barCaptionEyebrow {
+    font-size: 0.72rem;
+    font-weight: 600;
+    letter-spacing: 0.06em;
+    text-transform: uppercase;
+    color: var(--text-muted, #6d685f);
+  }
+
+  .barCaptionCount {
+    font-size: 0.95rem;
+    font-weight: 600;
+    line-height: 1.3;
+    color: var(--text-primary, #1a1612);
   }
 }