feat(mobile): iOS polish — theme-color, safe-area, dvh, tap-highlight

MOB-19: Add a viewport Viewport export with viewportFit: 'cover' and
themeColor entries for light (#faf7f2) / dark (#1a1612), plus the
appleWebApp metadata for the home-screen status bar style and title.
Manifest's stale #3b82f6 theme_color updated to match brand cream.

MOB-20: Apply env(safe-area-inset-*) to the sticky chrome — the top
header gets max(padding, inset-left/right) so the logo and tab links
clear the notch in landscape; the bottom tab bar already had
inset-bottom and now also gets inset-left/right.

MOB-21: Replace 100vh with 100dvh in body min-height, modal max-heights,
the map view container, and the fullscreen map. Older engines fall
back via the duplicated vh declaration.

MOB-22: Set -webkit-tap-highlight-color: transparent on body to
suppress the iOS Safari grey flash; add a generic touch-pointer
:active rule (opacity 0.7) so taps still register visually on plain
anchors and bare buttons. Components with their own :active styling
are unaffected.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

nextjs-app/public/manifest.json

@@ -1,11 +1,11 @@
 {
   "name": "SchoolCompare",
   "short_name": "SchoolCompare",
-  "description": "Compare primary school KS2 performance across England",
+  "description": "Compare primary and secondary school performance across England",
   "start_url": "/",
   "display": "standalone",
-  "background_color": "#ffffff",
-  "theme_color": "#3b82f6",
+  "background_color": "#faf7f2",
+  "theme_color": "#faf7f2",
   "icons": [
     {
       "src": "/favicon.svg",