address code review: POI order matches plan, self-documenting height reserve

Reorders the Verbrannte Straße POIs to plan §8's authored sequence
(hunt, investigate, search, then the scout) — purely a keyboard tab-order
fix, since hotspots are placed by percentage, not list order.

Rewrites the location page's viewport-height reserve as a calc() over the
same rem values the top bar and footer already declare as their own
min-block-size, with file:line pointers to both, instead of an opaque
191px constant. Doesn't remove the underlying coupling (still no
ResizeObserver / shared token), but a future edit to either component's
minimum height now has a documented, unit-matching term to update instead
of an unexplained magic number.

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

apps/web/src/app/features/world/location-page/location-page.component.spec.ts

@@ -85,9 +85,9 @@ describe('LocationPageComponent', () => {
     expect(hotspots).toHaveLength(4);
     expect([...hotspots].map((poi) => poi.querySelector('button')?.dataset['poi'])).toEqual([
       'hunt-area',
-      'wounded-scout',
       'inspect-tracks',
       'search-abandoned-wagon',
+      'wounded-scout',
     ]);
   });